Type61t-74.mws

> read `/Documents and Settings/ibuki/My Documents/ESC/ESC.mpl`;
ESC();
 

`Elliptic Surface Calculator v.1.01. c.1990-2008` (1)
 

> with(algcurves):
 

TypeNo.61 

> qc[61]:=(x^2+y^2-x*z)^2-x^2*z^2-y^2*z^2;
 

`:=`(qc[61], `+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(x, `*`(z)))), 2)), `-`(`*`(`^`(x, 2), `*`(`^`(z, 2)))), `-`(`*`(`^`(y, 2), `*`(`^`(z, 2)))))) (1.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[61]),x,y);
 

Warning, the name changecoords has been redefined
 

Plot_2d
 

> singularities(subs(z=1,qc[61]),x,y);
 

{[[0, 0, 1], 2, 1, 1], [[RootOf(`+`(`*`(`^`(_Z, 2)), 1)), 1, 0], 2, 1, 1]} (1.2)
 

> subs(y=t*x+z,qc[61]);
 

`+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(`^`(`+`(`*`(t, `*`(x)), z), 2)), `-`(`*`(x, `*`(z)))), 2)), `-`(`*`(`^`(x, 2), `*`(`^`(z, 2)))), `-`(`*`(`^`(`+`(`*`(t, `*`(x)), z), 2), `*`(`^`(z, 2))))) (1.3)
 

> Q61:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q61, `+`(`*`(2, `*`(`+`(`-`(1), t), `*`(U))), `*`(`+`(2, `*`(5, `*`(`^`(t, 2))), `-`(`*`(4, `*`(t)))), `*`(`^`(U, 2))), `*`(`^`(`+`(1, `*`(`^`(t, 2))), 2), `*`(`^`(U, 4))), `*`(2, `*`(`+`(`*`(2, ... (1.4)
 

> subs(U=0,Q61);
simplify(%);
 

0 (1.5)
 

0 (1.5)
 

> Quartic_to_Weierstrass(Q61,[0,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(`+`(`-`(1), t), 2), `*`(`^`(`+`(1, `*`(`^`(t, 2))), 2), `*`(`^`(Z, 3)))))), `-`(`*`(4, `*`(`+`(`-`(1), t), `*`(`+`(`*`(2, `*`(t)), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(`+`(`-`(1), t), 2), `*`(`^`(`+`(1, `*`(`^`(t, 2))), 2), `*`(`^`(Z, 3)))))), `-`(`*`(4, `*`(`+`(`-`(1), t), `*`(`+`(`*`(2, `*`(t)), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(`+`(`-`(1), t), 2), `*`(`^`(`+`(1, `*`(`^`(t, 2))), 2), `*`(`^`(Z, 3)))))), `-`(`*`(4, `*`(`+`(`-`(1), t), `*`(`+`(`*`(2, `*`(t)), `...
(1.6)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(`+`(`-`(1), t), 2), `*`(`^`(`+`(1, `*`(`^`(t, 2))), 2), `*`(`^`(Z, 3)))))), `-`(`*`(4, `*`(`+`(`-`(1), t), `*`(`+`(`*`(2, `*`(t)), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(`+`(`-`(1), t), 2), `*`(`^`(`+`(1, `*`(`^`(t, 2))), 2), `*`(`^`(Z, 3)))))), `-`(`*`(4, `*`(`+`(`-`(1), t), `*`(`+`(`*`(2, `*`(t)), `...
(1.7)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(`+`(`-`(1), t), 2), `*`(`^`(`+`(1, `*`(`^`(t, 2))), 2), `*`(`^`(Z, 3)))))), `-`(`*`(4, `*`(`+`(`-`(1), t), `*`(`+`(`*`(2, `*`(t)), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(`+`(`-`(1), t), 2), `*`(`^`(`+`(1, `*`(`^`(t, 2))), 2), `*`(`^`(Z, 3)))))), `-`(`*`(4, `*`(`+`(`-`(1), t), `*`(`+`(`*`(2, `*`(t)), `...
(1.8)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (1.9)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(2, `*`(5, `*`(`^`(t, 2))), `-`(`*`(4, `*`(t)))), `*`(`^`(x, 2))), `*`(4, `*`(`+`(`-`(1), t), `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`+`(1, `*`(`^`(t, 2))), `... (1.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(2, `*`(5, `*`(`^`(t, 2))), `-`(`*`(4, `*`(t)))), `*`(`^`(x, 2))), `*`(4, `*`(`+`(`-`(1), t), `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`+`(1, `*`(`^`(t, 2))), `... (1.10)
 

Discriminant = `+`(`*`(256, `*`(`+`(`*`(2, `*`(t)), `-`(11)), `*`(`^`(`+`(`-`(1), t), 2), `*`(`^`(`+`(1, `*`(`^`(t, 2))), 3)))))) (1.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(t, 2), 3), `*`(`^`(`+`(`*`(`^`(t, 3)), `-`(`*`(6, `*`(`^`(t, 2)))), `*`(12, `*`(t)), `-`(4)), 3)))), `*`(`+`(`*`(2, `*`(t)), `-`(11)), `*`(`^`(`+... (1.10)
 

`
` (1.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.61. (1.10)
 

`
` (1.10)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (1.10)
 

`
` (1.10)
 

The rank of the Mordell-Weil group over C is 1. (1.10)
 

` ` (1.10)
 

TypeNo.62 

> qc[62]:=(x^3-y^2*z)*y;
 

`:=`(qc[62], `*`(`+`(`*`(`^`(x, 3)), `-`(`*`(`^`(y, 2), `*`(z)))), `*`(y))) (2.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[62]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[62]),x,y);
 

{[[0, 0, 1], 3, 4, 2]} (2.2)
 

> subs(y=t*(x-z),qc[62]);
 

`*`(`+`(`*`(`^`(x, 3)), `-`(`*`(`^`(t, 2), `*`(`^`(`+`(x, `-`(z)), 2), `*`(z))))), `*`(t, `*`(`+`(x, `-`(z))))) (2.3)
 

> Q62:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q62, `+`(`-`(`*`(3, `*`(`^`(t, 3), `*`(U)))), `-`(`*`(t, `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(U, 3))))), `*`(3, `*`(`^`(t, 3), `*`(`^`(U, 2)))), `*`(t, `*`(`^`(U, 4))), `*`(`^`(t, 3)))) (2.4)
 

> subs(U=1,Q62);
simplify(%);
 

`+`(`*`(`^`(t, 3)), `-`(`*`(t, `*`(`+`(`*`(`^`(t, 2)), 1)))), t) (2.5)
 

0 (2.5)
 

> Quartic_to_Weierstrass(Q62,[1,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(3, `*`(t, `*`(`^`(X, 2), `*`(Z))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(Z, 2), `*`(X)))), `-`(`*`(`^`(t, 3), `*`(`^`(Z, 3)...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(3, `*`(t, `*`(`^`(X, 2), `*`(Z))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(Z, 2), `*`(X)))), `-`(`*`(`^`(t, 3), `*`(`^`(Z, 3)...
(2.6)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(3, `*`(t, `*`(`^`(X, 2), `*`(Z))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(Z, 2), `*`(X)))), `-`(`*`(`^`(t, 3), `*`(`^`(Z, 3)... (2.7)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(3, `*`(t, `*`(`^`(X, 2), `*`(Z))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(Z, 2), `*`(X)))), `-`(`*`(`^`(t, 3), `*`(`^`(Z, 3)... (2.8)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (2.9)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(3, `*`(t, `*`(`^`(x, 2)))), `-`(`*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(x)))), `*`(`^`(t, 3))) (2.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(3, `*`(t, `*`(`^`(x, 2)))), `-`(`*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(x)))), `*`(`^`(t, 3))) (2.10)
 

Discriminant = `+`(`*`(16, `*`(`^`(t, 10), `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(27)))))) (2.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(6912, `*`(`^`(t, 2))), `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(27))))) (2.10)
 

`
` (2.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.62. (2.10)
 

`
` (2.10)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (2.10)
 

`
` (2.10)
 

The rank of the Mordell-Weil group over C is 0. (2.10)
 

` ` (2.10)
 

TypeNo.63 

 

> qc[63]:=(y*z-x^2)^2-y^3*x;
 

`:=`(qc[63], `+`(`*`(`^`(`+`(`*`(y, `*`(z)), `-`(`*`(`^`(x, 2)))), 2)), `-`(`*`(`^`(y, 3), `*`(x))))) (3.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[63]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[63]),x,y);
 

{[[0, 0, 1], 2, 3, 1]} (3.2)
 

> subs(z=t*x,qc[63]);
 

`+`(`*`(`^`(`+`(`*`(y, `*`(t, `*`(x))), `-`(`*`(`^`(x, 2)))), 2)), `-`(`*`(`^`(y, 3), `*`(x)))) (3.3)
 

> Q63:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q63, `+`(`*`(`^`(t, 2), `*`(`^`(U, 2))), `-`(`*`(2, `*`(t, `*`(`^`(U, 3))))), `*`(`^`(U, 4)), `-`(U))) (3.4)
 

> subs(U=0,Q63);
simplify(%);
 

0 (3.5)
 

0 (3.5)
 

> Quartic_to_Weierstrass(Q63,[0,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`^`(t, 2), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(2, `*`(t, `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(Z, 3)))), {X = `+`(`-`(U)), Y = `+`(`-`(V)), Z = ... (3.6)
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
(3.7)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`^`(t, 2), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(2, `*`(t, `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(Z, 3)))), {x = X, y = Y, z = Z}, [x, y, z] (3.8)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`^`(t, 2), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(2, `*`(t, `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(Z, 3)))) (3.9)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (3.10)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`^`(t, 2), `*`(`^`(x, 2))), `*`(2, `*`(t, `*`(x))), 1) (3.10)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`^`(t, 2), `*`(`^`(x, 2))), `*`(2, `*`(t, `*`(x))), 1) (3.11)
 

Discriminant = `+`(`*`(64, `*`(`^`(t, 3))), `-`(432)) (3.11)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(256, `*`(`^`(t, 3), `*`(`^`(`+`(`*`(`^`(t, 3)), `-`(6)), 3)))), `*`(`+`(`*`(4, `*`(`^`(t, 3))), `-`(27))))) (3.11)
 

`
` (3.11)
 

This is a rational elliptic surface; Oguiso-Shioda type No.63. (3.11)
 

`
` (3.11)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (3.11)
 

`
` (3.11)
 

The rank of the Mordell-Weil group over C is 0. (3.11)
 

` ` (3.11)
 

TypeNo.64 

> qc[64]:=(x^2-y*z+y^2)*(x^2-y*z-y^2);
 

`:=`(qc[64], `*`(`+`(`*`(`^`(x, 2)), `-`(`*`(y, `*`(z))), `*`(`^`(y, 2))), `*`(`+`(`*`(`^`(x, 2)), `-`(`*`(y, `*`(z))), `-`(`*`(`^`(y, 2))))))) (4.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[64]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[64]),x,y);
 

{[[0, 0, 1], 2, 4, 2]} (4.2)
 

> subs(y=t*(x-z),qc[64]);
 

`*`(`+`(`*`(`^`(x, 2)), `-`(`*`(t, `*`(`+`(x, `-`(z)), `*`(z)))), `*`(`^`(t, 2), `*`(`^`(`+`(x, `-`(z)), 2)))), `*`(`+`(`*`(`^`(x, 2)), `-`(`*`(t, `*`(`+`(x, `-`(z)), `*`(z)))), `-`(`*`(`^`(t, 2), `*`... (4.3)
 

> Q64:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q64, `+`(`*`(2, `*`(`^`(t, 2), `*`(`+`(`-`(1), `*`(2, `*`(`^`(t, 2)))), `*`(U)))), `-`(`*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(U, 4)))))), `-`(`*`(t, `*`(`+`(`*`(6,...
`:=`(Q64, `+`(`*`(2, `*`(`^`(t, 2), `*`(`+`(`-`(1), `*`(2, `*`(`^`(t, 2)))), `*`(U)))), `-`(`*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(U, 4)))))), `-`(`*`(t, `*`(`+`(`*`(6,...
(4.4)
 

> subs(U=1,Q64);
simplify(%);
 

`+`(`*`(2, `*`(`^`(t, 2), `*`(`+`(`-`(1), `*`(2, `*`(`^`(t, 2))))))), `-`(`*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`+`(`*`(`^`(t, 2)), 1))))), `-`(`*`(t, `*`(`+`(`*`(6, `*`(`^`(t, 3))), `-`(t), `-`(2)))...
`+`(`*`(2, `*`(`^`(t, 2), `*`(`+`(`-`(1), `*`(2, `*`(`^`(t, 2))))))), `-`(`*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`+`(`*`(`^`(t, 2)), 1))))), `-`(`*`(t, `*`(`+`(`*`(6, `*`(`^`(t, 3))), `-`(t), `-`(2)))...
(4.5)
 

1 (4.5)
 

> Quartic_to_Weierstrass(Q64,[1,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`-`(`*`(2, `*`(t))), 4), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(4, `*`(t))), 8), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(2, `*`(`^`(X, 2), `*`(Z))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`-`(`*`(2, `*`(t))), 4), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(4, `*`(t))), 8), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(2, `*`(`^`(X, 2), `*`(Z))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`-`(`*`(2, `*`(t))), 4), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(4, `*`(t))), 8), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(2, `*`(`^`(X, 2), `*`(Z))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`-`(`*`(2, `*`(t))), 4), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(4, `*`(t))), 8), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(2, `*`(`^`(X, 2), `*`(Z))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`-`(`*`(2, `*`(t))), 4), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(4, `*`(t))), 8), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(2, `*`(`^`(X, 2), `*`(Z))))...
(4.6)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(`^`(t, 2)), `-`(`*`(4, `*`(t))), 6), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(4, `*`(`+`(`*`(2, `*`(`^`(t, 4))), `-`(`*`(4, `*`(t))), `*`(`^`(...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(`^`(t, 2)), `-`(`*`(4, `*`(t))), 6), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(4, `*`(`+`(`*`(2, `*`(`^`(t, 4))), `-`(`*`(4, `*`(t))), `*`(`^`(...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(`^`(t, 2)), `-`(`*`(4, `*`(t))), 6), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(4, `*`(`+`(`*`(2, `*`(`^`(t, 4))), `-`(`*`(4, `*`(t))), `*`(`^`(...
(4.7)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(`^`(t, 2)), `-`(`*`(4, `*`(t))), 6), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(4, `*`(`+`(`*`(2, `*`(`^`(t, 4))), `-`(`*`(4, `*`(t))), `*`(`^`(...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(`^`(t, 2)), `-`(`*`(4, `*`(t))), 6), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(4, `*`(`+`(`*`(2, `*`(`^`(t, 4))), `-`(`*`(4, `*`(t))), `*`(`^`(...
(4.8)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (4.9)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`*`(`^`(t, 2)), `-`(`*`(4, `*`(t))), 6), `*`(`^`(x, 2))), `*`(`+`(`*`(4, `*`(`^`(t, 4))), `*`(4, `*`(`^`(t, 2))), `-`(`*`(16, `*`(t))), 12), `*`(x)), `*`(8... (4.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`*`(`^`(t, 2)), `-`(`*`(4, `*`(t))), 6), `*`(`^`(x, 2))), `*`(`+`(`*`(4, `*`(`^`(t, 4))), `*`(4, `*`(`^`(t, 2))), `-`(`*`(16, `*`(t))), 12), `*`(x)), `*`(8... (4.10)
 

Discriminant = `+`(`-`(`*`(256, `*`(`^`(t, 10), `*`(`+`(`*`(3, `*`(t)), 4), `*`(`+`(`*`(5, `*`(t)), `-`(4)))))))) (4.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(`-`(16), `*`(11, `*`(`^`(t, 2))), `*`(8, `*`(t))), 3))), `*`(`^`(t, 4), `*`(`+`(`*`(3, `*`(t)), 4), `*`(`+`(`*`(5, `*`(t)), `-`(4))))))) (4.10)
 

`
` (4.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.64. (4.10)
 

`
` (4.10)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (4.10)
 

`
` (4.10)
 

The rank of the Mordell-Weil group over C is 0. (4.10)
 

` ` (4.10)
 

 

TypeNo.65 

> qc[65]:=x^4-y^3*z;
 

`:=`(qc[65], `+`(`*`(`^`(x, 4)), `-`(`*`(`^`(y, 3), `*`(z))))) (5.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[65]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[65]),x,y);
 

{[[0, 0, 1], 3, 3, 1]} (5.2)
 

> subs(z=t*y,qc[65]);
 

`+`(`*`(`^`(x, 4)), `-`(`*`(`^`(y, 4), `*`(t)))) (5.3)
 

> Q65:=mapfactor(subs({x=1,y=U},%),U);
 

`:=`(Q65, `+`(1, `-`(`*`(t, `*`(`^`(U, 4)))))) (5.4)
 

> subs(U=0,Q65);
simplify(%);
 

1 (5.5)
 

1 (5.5)
 

> Quartic_to_Weierstrass(Q65,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(t, `*`(X, `*`(`^`(Z, 2))))))), {X = `+`(`*`(2, `*`(`+`(V, 1), `*`(U)))), Z = `*`(`^`(U, 3)), Y = `+`(`*`(4, `*`(V)), 4)}, {U = `+`(`/`(`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(t, `*`(X, `*`(`^`(Z, 2))))))), {X = `+`(`*`(2, `*`(`+`(V, 1), `*`(U)))), Z = `*`(`^`(U, 3)), Y = `+`(`*`(4, `*`(V)), 4)}, {U = `+`(`/`(`...
(5.6)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(t, `*`(X, `*`(`^`(Z, 2))))))), {x = X, y = Y, z = Z}, [x, y, z] (5.7)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(t, `*`(X, `*`(`^`(Z, 2))))))) (5.8)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (5.9)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(4, `*`(t, `*`(x)))) (5.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(4, `*`(t, `*`(x)))) (5.10)
 

Discriminant = `+`(`-`(`*`(4096, `*`(`^`(t, 3))))) (5.10)
 

`+`(jay, `-`(invariant)) = 1728 (5.10)
 

`
` (5.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.65. (5.10)
 

`
` (5.10)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (5.10)
 

`
` (5.10)
 

The rank of the Mordell-Weil group over C is 0. (5.10)
 

` ` (5.10)
 

TypeNo.66 

> qc[66]:=(x^2+y^2-x*z)^2-x^2*z^2-y^2*z^2;
 

`:=`(qc[66], `+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(x, `*`(z)))), 2)), `-`(`*`(`^`(x, 2), `*`(`^`(z, 2)))), `-`(`*`(`^`(y, 2), `*`(`^`(z, 2)))))) (6.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[66]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[66]),x,y);
 

{[[0, 0, 1], 2, 1, 1], [[RootOf(`+`(`*`(`^`(_Z, 2)), 1)), 1, 0], 2, 1, 1]} (6.2)
 

> subs(z=t*x,qc[66]);
 

`+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(`^`(x, 2), `*`(t)))), 2)), `-`(`*`(`^`(x, 4), `*`(`^`(t, 2)))), `-`(`*`(`^`(y, 2), `*`(`^`(t, 2), `*`(`^`(x, 2)))))) (6.3)
 

> Q66:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q66, `+`(`-`(`*`(`+`(`*`(`^`(t, 2)), `-`(2), `*`(2, `*`(t))), `*`(`^`(U, 2)))), `-`(`*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(U, 4)))), 1)) (6.4)
 

> subs(U=0,Q66);
simplify(%);
 

1 (6.5)
 

1 (6.5)
 

> Quartic_to_Weierstrass(Q66,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(`^`(t, 2))), 2, `-`(`*`(2, `*`(t)))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`*`(8, `*`(t)), `-`(4)), `*`(X, `*`(`^`(Z, 2))))), `*`(...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(`^`(t, 2))), 2, `-`(`*`(2, `*`(t)))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`*`(8, `*`(t)), `-`(4)), `*`(X, `*`(`^`(Z, 2))))), `*`(...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(`^`(t, 2))), 2, `-`(`*`(2, `*`(t)))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`*`(8, `*`(t)), `-`(4)), `*`(X, `*`(`^`(Z, 2))))), `*`(...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(`^`(t, 2))), 2, `-`(`*`(2, `*`(t)))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`*`(8, `*`(t)), `-`(4)), `*`(X, `*`(`^`(Z, 2))))), `*`(...
(6.6)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(4, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`+`(`*`(`^`(t, 2)), `-`(2), `*`(2, `*`(t))), `*`(`^`(Z, 3))))), `*`(`+`(`*`(`^`(t, 2)), `-`(2), `*`(2, `*`(...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(4, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`+`(`*`(`^`(t, 2)), `-`(2), `*`(2, `*`(t))), `*`(`^`(Z, 3))))), `*`(`+`(`*`(`^`(t, 2)), `-`(2), `*`(2, `*`(...
(6.7)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(4, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`+`(`*`(`^`(t, 2)), `-`(2), `*`(2, `*`(t))), `*`(`^`(Z, 3))))), `*`(`+`(`*`(`^`(t, 2)), `-`(2), `*`(2, `*`(... (6.8)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (6.9)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(`^`(t, 2))), 2, `-`(`*`(2, `*`(t)))), `*`(`^`(x, 2))), `*`(`+`(`*`(8, `*`(t)), `-`(4)), `*`(x)), `-`(`*`(4, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`+... (6.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(`^`(t, 2))), 2, `-`(`*`(2, `*`(t)))), `*`(`^`(x, 2))), `*`(`+`(`*`(8, `*`(t)), `-`(4)), `*`(x)), `-`(`*`(4, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`+... (6.10)
 

Discriminant = `+`(`-`(`*`(256, `*`(`^`(t, 6), `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(`+`(t, 4), 2))))))) (6.10)
 

`+`(jay, `-`(invariant)) = `+`(`-`(`/`(`*`(16, `*`(`^`(`+`(t, `-`(2)), 3), `*`(`^`(`+`(`*`(`^`(t, 3)), `*`(6, `*`(`^`(t, 2))), `*`(12, `*`(t)), `-`(8)), 3)))), `*`(`^`(t, 6), `*`(`+`(`*`(2, `*`(t)), `... (6.10)
 

`
` (6.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.66. (6.10)
 

`
` (6.10)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (6.10)
 

`
` (6.10)
 

The rank of the Mordell-Weil group over C is 0. (6.10)
 

` ` (6.10)
 

TypeNo.67 

> qc[67]:=(x^2-y*z)^2-x^3*y;
 

`:=`(qc[67], `+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `-`(`*`(y, `*`(z)))), 2)), `-`(`*`(y, `*`(`^`(x, 3)))))) (7.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[67]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[67]),x,y);
 

{[[0, 0, 1], 2, 2, 1], [[0, 1, 0], 2, 1, 1]} (7.2)
 

> subs(y=t*(x+4*z)-16*z,qc[67]);
 

`+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `-`(`*`(`+`(`*`(t, `*`(`+`(x, `*`(4, `*`(z))))), `-`(`*`(16, `*`(z)))), `*`(z)))), 2)), `-`(`*`(`+`(`*`(t, `*`(`+`(x, `*`(4, `*`(z))))), `-`(`*`(16, `*`(z)))), `*`(`^`(... (7.3)
 

> Q67:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q67, `+`(`*`(8, `*`(t, `*`(`+`(t, `-`(4)), `*`(U)))), `-`(`*`(2, `*`(`+`(`-`(8), `*`(3, `*`(t))), `*`(`^`(U, 3))))), `-`(`*`(`+`(t, `-`(1)), `*`(`^`(U, 4)))), `*`(`+`(`-`(`*`(8, `*`(t))), 32, `*`...
`:=`(Q67, `+`(`*`(8, `*`(t, `*`(`+`(t, `-`(4)), `*`(U)))), `-`(`*`(2, `*`(`+`(`-`(8), `*`(3, `*`(t))), `*`(`^`(U, 3))))), `-`(`*`(`+`(t, `-`(1)), `*`(`^`(U, 4)))), `*`(`+`(`-`(`*`(8, `*`(t))), 32, `*`...
(7.4)
 

> subs(U=-4,Q67);
simplify(%);
 

`+`(`-`(`*`(32, `*`(t, `*`(`+`(t, `-`(4)))))), `-`(256), `*`(16, `*`(`^`(t, 2))), `*`(16, `*`(`^`(`+`(t, `-`(4)), 2)))) (7.5)
 

0 (7.5)
 

> Quartic_to_Weierstrass(Q67,[-4,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(64), `-`(`*`(32, `*`(t))), `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(2560, `*`(t, `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(`+`(`-`(`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(64), `-`(`*`(32, `*`(t))), `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(2560, `*`(t, `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(`+`(`-`(`...
(7.6)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(64), `-`(`*`(32, `*`(t))), `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(2560, `*`(t, `*`(X, `*`(`^`(Z, 2)))))), `*`(65536, `*`(`+...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(64), `-`(`*`(32, `*`(t))), `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(2560, `*`(t, `*`(X, `*`(`^`(Z, 2)))))), `*`(65536, `*`(`+...
(7.7)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(64), `-`(`*`(32, `*`(t))), `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(2560, `*`(t, `*`(X, `*`(`^`(Z, 2)))))), `*`(65536, `*`(`+... (7.8)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (7.9)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(64), `-`(`*`(32, `*`(t))), `*`(`^`(t, 2))), `*`(`^`(x, 2))), `*`(2560, `*`(t, `*`(x))), `-`(`*`(65536, `*`(t))), 65536) (7.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(64), `-`(`*`(32, `*`(t))), `*`(`^`(t, 2))), `*`(`^`(x, 2))), `*`(2560, `*`(t, `*`(x))), `-`(`*`(65536, `*`(t))), 65536) (7.10)
 

Discriminant = `+`(`*`(4194304, `*`(`+`(`*`(`^`(t, 2)), `-`(`*`(52, `*`(t))), 176), `*`(`^`(`+`(t, `-`(4)), 5))))) (7.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(`^`(`+`(4096, `-`(`*`(3584, `*`(t))), `*`(896, `*`(`^`(t, 2))), `-`(`*`(64, `*`(`^`(t, 3)))), `*`(`^`(t, 4))), 3)), `*`(1024, `*`(`+`(`*`(`^`(t, 2)), `-`(`*`(52,... (7.10)
 

`
` (7.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.67. (7.10)
 

`
` (7.10)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (7.10)
 

`
` (7.10)
 

The rank of the Mordell-Weil group over C is 0. (7.10)
 

` ` (7.10)
 

TypeNo.68 

> qc[68]:=(x^2+3*y^2-x*z)^2-x^2*z^2-3*y^2*z^2;
 

`:=`(qc[68], `+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(3, `*`(`^`(y, 2))), `-`(`*`(x, `*`(z)))), 2)), `-`(`*`(`^`(x, 2), `*`(`^`(z, 2)))), `-`(`*`(3, `*`(`^`(y, 2), `*`(`^`(z, 2))))))) (8.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[68]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[68]),x,y);
 

{[[RootOf(`+`(`*`(`^`(_Z, 2)), 3)), 1, 0], 2, 1, 1], [[0, 0, 1], 2, 1, 1]} (8.2)
 

> subs(z=t*(x-y)-4*y,qc[68]);
 

`+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(3, `*`(`^`(y, 2))), `-`(`*`(x, `*`(`+`(`*`(t, `*`(`+`(x, `-`(y)))), `-`(`*`(4, `*`(y)))))))), 2)), `-`(`*`(`^`(x, 2), `*`(`^`(`+`(`*`(t, `*`(`+`(x, `-`(y)))), `-`(`... (8.3)
 

> Q68:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q68, `+`(`*`(6, `*`(`+`(t, 4), `*`(`+`(t, 1), `*`(U)))), `-`(`*`(3, `*`(`+`(`*`(`^`(t, 2)), `-`(2), `*`(2, `*`(t))), `*`(`^`(U, 2))))), `*`(2, `*`(`+`(t, 4), `*`(`^`(U, 3)))), `-`(`*`(`+`(`*`(2, ...
`:=`(Q68, `+`(`*`(6, `*`(`+`(t, 4), `*`(`+`(t, 1), `*`(U)))), `-`(`*`(3, `*`(`+`(`*`(`^`(t, 2)), `-`(2), `*`(2, `*`(t))), `*`(`^`(U, 2))))), `*`(2, `*`(`+`(t, 4), `*`(`^`(U, 3)))), `-`(`*`(`+`(`*`(2, ...
(8.4)
 

> subs(U=1,Q68);
simplify(%);
 

`+`(`*`(6, `*`(`+`(t, 4), `*`(`+`(t, 1)))), `-`(`*`(6, `*`(`^`(t, 2)))), `-`(24), `-`(`*`(30, `*`(t)))) (8.5)
 

0 (8.5)
 

> Quartic_to_Weierstrass(Q68,[1,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(3, `*`(`+`(t, 6), `*`(`+`(t, `-`(2)), `*`(`^`(X, 2), `*`(Z))))), `*`(256, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(`+`(t, 4), 2), `*`(`^`(Z, 3)))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(3, `*`(`+`(t, 6), `*`(`+`(t, `-`(2)), `*`(`^`(X, 2), `*`(Z))))), `*`(256, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(`+`(t, 4), 2), `*`(`^`(Z, 3)))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(3, `*`(`+`(t, 6), `*`(`+`(t, `-`(2)), `*`(`^`(X, 2), `*`(Z))))), `*`(256, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(`+`(t, 4), 2), `*`(`^`(Z, 3)))))...
(8.6)
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
(8.7)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(3, `*`(`+`(t, 6), `*`(`+`(t, `-`(2)), `*`(`^`(X, 2), `*`(Z))))), `*`(256, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(`+`(t, 4), 2), `*`(`^`(Z, 3)))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(3, `*`(`+`(t, 6), `*`(`+`(t, `-`(2)), `*`(`^`(X, 2), `*`(Z))))), `*`(256, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(`+`(t, 4), 2), `*`(`^`(Z, 3)))))...
(8.8)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(3, `*`(`+`(t, 6), `*`(`+`(t, `-`(2)), `*`(`^`(X, 2), `*`(Z))))), `*`(256, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(`+`(t, 4), 2), `*`(`^`(Z, 3)))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(3, `*`(`+`(t, 6), `*`(`+`(t, `-`(2)), `*`(`^`(X, 2), `*`(Z))))), `*`(256, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(`+`(t, 4), 2), `*`(`^`(Z, 3)))))...
(8.9)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (8.10)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(3, `*`(`+`(t, 6), `*`(`+`(t, `-`(2)), `*`(`^`(x, 2)))))), `-`(`*`(96, `*`(`+`(t, 4), `*`(`+`(t, `-`(2)), `*`(x))))), `-`(`*`(256, `*`(`+`(`*`(2, `*`(t)), `... (8.10)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(3, `*`(`+`(t, 6), `*`(`+`(t, `-`(2)), `*`(`^`(x, 2)))))), `-`(`*`(96, `*`(`+`(t, 4), `*`(`+`(t, `-`(2)), `*`(x))))), `-`(`*`(256, `*`(`+`(`*`(2, `*`(t)), `... (8.11)
 

Discriminant = `+`(`-`(`*`(884736, `*`(`^`(`+`(t, 4), 3), `*`(`^`(`+`(`*`(`^`(t, 2)), `*`(2, `*`(t)), 4), 3)))))) (8.11)
 

`+`(jay, `-`(invariant)) = `+`(`-`(`/`(`*`(27, `*`(`^`(`+`(t, `-`(2)), 3), `*`(`^`(`+`(t, 2), 3), `*`(`^`(`+`(`*`(`^`(t, 2)), `*`(8, `*`(t)), 28), 3))))), `*`(8, `*`(`^`(`+`(t, 4), 3), `*`(`^`(`+`(`*`... (8.11)
 

`
` (8.11)
 

This is a rational elliptic surface; Oguiso-Shioda type No.68. (8.11)
 

`
` (8.11)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (8.11)
 

`
` (8.11)
 

The rank of the Mordell-Weil group over C is 0. (8.11)
 

` ` (8.11)
 

TypeNo.69 

> qc[69]:=x^4-y^3*z;
 

>
 

`:=`(qc[69], `+`(`*`(`^`(x, 4)), `-`(`*`(`^`(y, 3), `*`(z))))) (9.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[69]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[69]),x,y);
 

{[[0, 0, 1], 3, 3, 1]} (9.2)
 

> subs(z=t*x,qc[69]);
 

`+`(`*`(`^`(x, 4)), `-`(`*`(`^`(y, 3), `*`(t, `*`(x))))) (9.3)
 

> Q69:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q69, `+`(`*`(`^`(U, 4)), `-`(`*`(t, `*`(U))))) (9.4)
 

> subs(U=0,Q69);
simplify(%);
 

0 (9.5)
 

0 (9.5)
 

> Quartic_to_Weierstrass(Q69,[0,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`^`(t, 2), `*`(`^`(Z, 3))))), {X = `+`(`-`(`*`(t, `*`(U)))), Y = `+`(`-`(`*`(t, `*`(V)))), Z = `*`(`^`(U, 2))}, {V = `+`(`-`(`/`(`*`(Y, `*`(t))... (9.6)
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
(9.7)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`^`(t, 2), `*`(`^`(Z, 3))))), {x = X, y = Y, z = Z}, [x, y, z] (9.8)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`^`(t, 2), `*`(`^`(Z, 3))))) (9.9)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (9.10)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`^`(t, 2))) (9.10)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`^`(t, 2))) (9.11)
 

Discriminant = `+`(`-`(`*`(432, `*`(`^`(t, 4))))) (9.11)
 

`+`(jay, `-`(invariant)) = 0 (9.11)
 

`
` (9.11)
 

This is a rational elliptic surface; Oguiso-Shioda type No.69. (9.11)
 

`
` (9.11)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (9.11)
 

`
` (9.11)
 

The rank of the Mordell-Weil group over C is 0. (9.11)
 

` ` (9.11)
 

TypeNo.70 

> qc[70]:=(x^2+y^2-z^2)*(y+z)*(y-z);
 

`:=`(qc[70], `*`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(`^`(z, 2)))), `*`(`+`(y, z), `*`(`+`(y, `-`(z)))))) (10.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[70]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[70]),x,y);
 

{[[0, 1, 1], 2, 2, 2], [[1, 0, 0], 2, 1, 2], [[0, -1, 1], 2, 2, 2]} (10.2)
 

> subs(y=t*x,qc[70]);
 

`*`(`+`(`*`(`^`(x, 2)), `*`(`^`(t, 2), `*`(`^`(x, 2))), `-`(`*`(`^`(z, 2)))), `*`(`+`(`*`(t, `*`(x)), z), `*`(`+`(`*`(t, `*`(x)), `-`(z))))) (10.3)
 

> Q70:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q70, `+`(`-`(`*`(`+`(1, `*`(2, `*`(`^`(t, 2)))), `*`(`^`(U, 2)))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(U, 4)))), 1)) (10.4)
 

> subs(U=0,Q70);
simplify(%);
 

1 (10.5)
 

1 (10.5)
 

> Quartic_to_Weierstrass(Q70,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(1), `-`(`*`(2, `*`(`^`(t, 2))))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(X, `*`(`^`(Z, 2))))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(1), `-`(`*`(2, `*`(`^`(t, 2))))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(X, `*`(`^`(Z, 2))))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(1), `-`(`*`(2, `*`(`^`(t, 2))))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(X, `*`(`^`(Z, 2))))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(1), `-`(`*`(2, `*`(`^`(t, 2))))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(X, `*`(`^`(Z, 2))))))...
(10.6)
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
(10.7)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(1, `*`(2, `*`(`^`(t, 2)))), `*`(`+`(`*`(...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(1, `*`(2, `*`(`^`(t, 2)))), `*`(`+`(`*`(...
(10.8)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(1, `*`(2, `*`(`^`(t, 2)))), `*`(`+`(`*`(... (10.9)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (10.10)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(1), `-`(`*`(2, `*`(`^`(t, 2))))), `*`(`^`(x, 2))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(x))))), `*`(4, `*`(`^`(t, 2), `*`(`+`(1, `... (10.10)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(1), `-`(`*`(2, `*`(`^`(t, 2))))), `*`(`^`(x, 2))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(x))))), `*`(4, `*`(`^`(t, 2), `*`(`+`(1, `... (10.11)
 

Discriminant = `+`(`*`(256, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))))) (10.11)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(1, `*`(16, `*`(`^`(t, 2))), `*`(16, `*`(`^`(t, 4)))), 3))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))))) (10.11)
 

`
` (10.11)
 

This is a rational elliptic surface; Oguiso-Shioda type No.70. (10.11)
 

`
` (10.11)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (10.11)
 

`
` (10.11)
 

The rank of the Mordell-Weil group over C is 0. (10.11)
 

` ` (10.11)
 

>
 

TypeNo.71 

> qc[71]:=x^4+y^4-x*y^2*z;
 

`:=`(qc[71], `+`(`*`(`^`(x, 4)), `*`(`^`(y, 4)), `-`(`*`(x, `*`(`^`(y, 2), `*`(z)))))) (2)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[71]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[71]),x,y);
 

{[[0, 0, 1], 3, 3, 2]} (3)
 

> subs(z=t*x,qc[71]);
 

`+`(`*`(`^`(x, 4)), `*`(`^`(y, 4)), `-`(`*`(`^`(x, 2), `*`(`^`(y, 2), `*`(t))))) (4)
 

> Q71:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q71, `+`(`*`(`^`(U, 4)), 1, `-`(`*`(`^`(U, 2), `*`(t))))) (5)
 

> subs(U=0,Q71);
simplify(%);
 

1 (6)
 

1 (6)
 

> Quartic_to_Weierstrass(Q71,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(t, `*`(`^`(X, 2), `*`(Z))), `*`(4, `*`(X, `*`(`^`(Z, 2)))), `-`(`*`(4, `*`(t, `*`(`^`(Z, 3)))))), {X = `+`(`*`(2, `*`(`+`(V, 1), `*`(U)))), Z = `*`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(t, `*`(`^`(X, 2), `*`(Z))), `*`(4, `*`(X, `*`(`^`(Z, 2)))), `-`(`*`(4, `*`(t, `*`(`^`(Z, 3)))))), {X = `+`(`*`(2, `*`(`+`(V, 1), `*`(U)))), Z = `*`...
(7)
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
(8)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(t, `*`(`^`(X, 2), `*`(Z))), `*`(4, `*`(X, `*`(`^`(Z, 2)))), `-`(`*`(4, `*`(t, `*`(`^`(Z, 3)))))), {x = X, y = Y, z = Z}, [x, y, z] (9)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(t, `*`(`^`(X, 2), `*`(Z))), `*`(4, `*`(X, `*`(`^`(Z, 2)))), `-`(`*`(4, `*`(t, `*`(`^`(Z, 3)))))) (10)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (11)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(t, `*`(`^`(x, 2)))), `-`(`*`(4, `*`(x))), `*`(4, `*`(t))) (11)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(t, `*`(`^`(x, 2)))), `-`(`*`(4, `*`(x))), `*`(4, `*`(t))) (12)
 

Discriminant = `+`(`*`(256, `*`(`^`(`+`(t, `-`(2)), 2), `*`(`^`(`+`(t, 2), 2))))) (12)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(`*`(`^`(t, 2)), 12), 3))), `*`(`^`(`+`(t, `-`(2)), 2), `*`(`^`(`+`(t, 2), 2))))) (12)
 

`
` (12)
 

This is a rational elliptic surface; Oguiso-Shioda type No.71. (12)
 

`
` (12)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (12)
 

`
` (12)
 

The rank of the Mordell-Weil group over C is 0. (12)
 

` ` (12)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(1), `-`(`*`(2, `*`(`^`(t, 2))))), `*`(`^`(x, 2))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(x))))), `*`(4, `*`(`^`(t, 2), `*`(`+`(1, `... 

Discriminant = `+`(`*`(256, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))))) 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(1, `*`(16, `*`(`^`(t, 2))), `*`(16, `*`(`^`(t, 4)))), 3))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))))) 

`
` 

This is a rational elliptic surface; Oguiso-Shioda type No.70. 

`
` 

Typesetting:-mrow(Typesetting:-mi( 

`
` 

TypeNo.72 

> qc[72]:=(x^2+y^2-z^2)*(y+z)*(y-z);
 

`:=`(qc[72], `*`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(`^`(z, 2)))), `*`(`+`(y, z), `*`(`+`(y, `-`(z)))))) (13)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[72]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[72]),x,y);
 

{[[0, 1, 1], 2, 2, 2], [[1, 0, 0], 2, 1, 2], [[0, -1, 1], 2, 2, 2]} (14)
 

> subs(y=t*(x-z)+z,qc[72]);
 

`*`(`+`(`*`(`^`(x, 2)), `*`(`^`(`+`(`*`(t, `*`(`+`(x, `-`(z)))), z), 2)), `-`(`*`(`^`(z, 2)))), `*`(`+`(`*`(t, `*`(`+`(x, `-`(z)))), `*`(2, `*`(z))), `*`(t, `*`(`+`(x, `-`(z)))))) (15)
 

> Q72:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q72, `+`(`-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(t, `-`(1)), `*`(`+`(t, `-`(2)), `*`(U)))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(U, 4)))), `-`(`*`(2, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(...
`:=`(Q72, `+`(`-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(t, `-`(1)), `*`(`+`(t, `-`(2)), `*`(U)))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(U, 4)))), `-`(`*`(2, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(...
(16)
 

> subs(U=1,Q72);
simplify(%);
 

`+`(`-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(t, `-`(1)), `*`(`+`(t, `-`(2))))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))), `-`(`*`(2, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(1, `*`(2, `*`(`^`(t, 2))))))))), `...
`+`(`-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(t, `-`(1)), `*`(`+`(t, `-`(2))))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))), `-`(`*`(2, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(1, `*`(2, `*`(`^`(t, 2))))))))), `...
(17)
 

0 (17)
 

> Quartic_to_Weierstrass(Q72,[1,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(t, 4), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(Z, 3)))))), `-`(`*`(t, `*`(`+`(`*`(5, `*`(t)), 4), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(4, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(t, 4), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(Z, 3)))))), `-`(`*`(t, `*`(`+`(`*`(5, `*`(t)), 4), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(4, ...
(18)
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
(19)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(t, 4), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(Z, 3)))))), `-`(`*`(t, `*`(`+`(`*`(5, `*`(t)), 4), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(4, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(t, 4), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(Z, 3)))))), `-`(`*`(t, `*`(`+`(`*`(5, `*`(t)), 4), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(4, ...
(20)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`^`(t, 4), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(Z, 3)))))), `-`(`*`(t, `*`(`+`(`*`(5, `*`(t)), 4), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(4, ... (21)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (22)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(t, `*`(`+`(`*`(5, `*`(t)), 4), `*`(`^`(x, 2)))), `*`(4, `*`(`^`(t, 2), `*`(`+`(t, 1, `*`(2, `*`(`^`(t, 2)))), `*`(x)))), `*`(4, `*`(`^`(t, 4), `*`(`+`(`*`(`^`(... (22)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(t, `*`(`+`(`*`(5, `*`(t)), 4), `*`(`^`(x, 2)))), `*`(4, `*`(`^`(t, 2), `*`(`+`(t, 1, `*`(2, `*`(`^`(t, 2)))), `*`(x)))), `*`(4, `*`(`^`(t, 4), `*`(`+`(`*`(`^`(... (23)
 

Discriminant = `+`(`*`(512, `*`(`^`(t, 7), `*`(`^`(`+`(t, `-`(2)), 4))))) (23)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(8, `*`(`^`(`+`(`*`(`^`(t, 2)), `*`(28, `*`(t)), 4), 3))), `*`(t, `*`(`^`(`+`(t, `-`(2)), 4))))) (23)
 

`
` (23)
 

This is a rational elliptic surface; Oguiso-Shioda type No.72. (23)
 

`
` (23)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (23)
 

`
` (23)
 

The rank of the Mordell-Weil group over C is 0. (23)
 

TypeNo.73 

> qc[73]:=(x^2+y^2-z^2)*(4*x^2+y^2-4*z^2);
 

`:=`(qc[73], `*`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(`^`(z, 2)))), `*`(`+`(`*`(4, `*`(`^`(x, 2))), `*`(`^`(y, 2)), `-`(`*`(4, `*`(`^`(z, 2)))))))) (24)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[73]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[73]),x,y);
 

{[[-1, 0, 1], 2, 2, 2], [[1, 0, 1], 2, 2, 2]} (25)
 

> subs(z=t*x,qc[73]);
 

`*`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(`^`(t, 2), `*`(`^`(x, 2))))), `*`(`+`(`*`(4, `*`(`^`(x, 2))), `*`(`^`(y, 2)), `-`(`*`(4, `*`(`^`(t, 2), `*`(`^`(x, 2)))))))) (26)
 

> Q73:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q73, `+`(`*`(4, `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(`+`(t, 1), 2), `*`(`^`(U, 4))))), `-`(`*`(5, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(U, 2)))))), 1)) (27)
 

> subs(U=0,Q73);
simplify(%);
 

1 (28)
 

1 (28)
 

> Quartic_to_Weierstrass(Q73,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(5, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, 2), `*`(Z))))), `*`(16, `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(`+`(t, 1), 2), `*`(X, `*`(`^`(Z, 2))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(5, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, 2), `*`(Z))))), `*`(16, `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(`+`(t, 1), 2), `*`(X, `*`(`^`(Z, 2))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(5, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, 2), `*`(Z))))), `*`(16, `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(`+`(t, 1), 2), `*`(X, `*`(`^`(Z, 2))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(5, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, 2), `*`(Z))))), `*`(16, `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(`+`(t, 1), 2), `*`(X, `*`(`^`(Z, 2))))...
(29)
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
(30)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(5, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, 2), `*`(Z))))), `*`(16, `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(`+`(t, 1), 2), `*`(X, `*`(`^`(Z, 2))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(5, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, 2), `*`(Z))))), `*`(16, `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(`+`(t, 1), 2), `*`(X, `*`(`^`(Z, 2))))...
(31)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(5, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, 2), `*`(Z))))), `*`(16, `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(`+`(t, 1), 2), `*`(X, `*`(`^`(Z, 2))))... (32)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (33)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(5, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(x, 2)))))), `-`(`*`(16, `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(`+`(t, 1), 2), `*`(x))))), `*`(80, `*`(`^`(`+`(t,... (33)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(5, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(x, 2)))))), `-`(`*`(16, `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(`+`(t, 1), 2), `*`(x))))), `*`(80, `*`(`^`(`+`(t,... (34)
 

Discriminant = `+`(`*`(82944, `*`(`^`(`+`(t, `-`(1)), 6), `*`(`^`(`+`(t, 1), 6))))) (34)
 

`+`(jay, `-`(invariant)) = `/`(1556068, 81) (34)
 

`
` (34)
 

This is a rational elliptic surface; Oguiso-Shioda type No.73. (34)
 

`
` (34)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (34)
 

`
` (34)
 

The rank of the Mordell-Weil group over C is 0. (34)
 

` ` (34)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(1), `-`(`*`(2, `*`(`^`(t, 2))))), `*`(`^`(x, 2))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(x))))), `*`(4, `*`(`^`(t, 2), `*`(`+`(1, `... 

Discriminant = `+`(`*`(256, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))))) 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(1, `*`(16, `*`(`^`(t, 2))), `*`(16, `*`(`^`(t, 4)))), 3))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))))) 

TypeNo.74 

> qc[74]:=(x^2+y^2-z^2)*(y+z)*(y-z);
 

`:=`(qc[74], `*`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(`^`(z, 2)))), `*`(`+`(y, z), `*`(`+`(y, `-`(z)))))) (35)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[74]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[74]),x,y);
 

{[[0, 1, 1], 2, 2, 2], [[1, 0, 0], 2, 1, 2], [[0, -1, 1], 2, 2, 2]} (36)
 

> subs(y=t*(x-z),qc[74]);
 

`*`(`+`(`*`(`^`(x, 2)), `*`(`^`(t, 2), `*`(`^`(`+`(x, `-`(z)), 2))), `-`(`*`(`^`(z, 2)))), `*`(`+`(`*`(t, `*`(`+`(x, `-`(z)))), z), `*`(`+`(`*`(t, `*`(`+`(x, `-`(z)))), `-`(z))))) (37)
 

> Q74:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q74, `+`(`-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(t, 1), `*`(`+`(t, `-`(1)), `*`(U)))))), `-`(`*`(2, `*`(`^`(t, 2), `*`(`+`(1, `*`(2, `*`(`^`(t, 2)))), `*`(`^`(U, 3)))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`...
`:=`(Q74, `+`(`-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(t, 1), `*`(`+`(t, `-`(1)), `*`(U)))))), `-`(`*`(2, `*`(`^`(t, 2), `*`(`+`(1, `*`(2, `*`(`^`(t, 2)))), `*`(`^`(U, 3)))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`...
(38)
 

> subs(U=1,Q74);
simplify(%);
 

`+`(`-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(t, 1), `*`(`+`(t, `-`(1))))))), `-`(`*`(2, `*`(`^`(t, 2), `*`(`+`(1, `*`(2, `*`(`^`(t, 2)))))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))), `*`(`+`(`-`(1), `*`...
`+`(`-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(t, 1), `*`(`+`(t, `-`(1))))))), `-`(`*`(2, `*`(`^`(t, 2), `*`(`+`(1, `*`(2, `*`(`^`(t, 2)))))))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))), `*`(`+`(`-`(1), `*`...
(39)
 

0 (39)
 

> Quartic_to_Weierstrass(Q74,[1,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(`^`(t, 2))), `-`(1)), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`^`(t, 2), `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(`^`(t, 2))), `-`(1)), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`^`(t, 2), `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(`...
(40)
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `...
(41)
 

> step5(%[1],{x=X,z=Z,y=Y},{x,y,z});
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(X, 2), `*`(Z))), `*`(4, `*`(`^`(t, 2), `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), ... (42)
 

> mapfactor(subs({X=X,Y=Y},%[1]),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(X, 2), `*`(Z))), `*`(4, `*`(`^`(t, 2), `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), ... (43)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (44)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(`^`(t, 2))), `-`(1)), `*`(`^`(x, 2))), `-`(`*`(4, `*`(`^`(t, 2), `*`(x)))), `*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))))) (44)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(`^`(t, 2))), `-`(1)), `*`(`^`(x, 2))), `-`(`*`(4, `*`(`^`(t, 2), `*`(x)))), `*`(4, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 1))))) (45)
 

Discriminant = `+`(`*`(256, `*`(`^`(t, 2), `*`(`^`(`+`(t, `-`(1)), 4), `*`(`^`(`+`(t, 1), 4)))))) (45)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(1, `*`(14, `*`(`^`(t, 2))), `*`(`^`(t, 4))), 3))), `*`(`^`(t, 2), `*`(`^`(`+`(t, `-`(1)), 4), `*`(`^`(`+`(t, 1), 4)))))) (45)
 

`
` (45)
 

This is a rational elliptic surface; Oguiso-Shioda type No.74. (45)
 

`
` (45)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (45)
 

`
` (45)
 

The rank of the Mordell-Weil group over C is 0. (45)
 

` ` (45)
 

>