Type51-60.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.51 

> qc[51]:=x^4+x^3*z-y^2*z^2;
 

`:=`(qc[51], `+`(`*`(`^`(x, 4)), `*`(`^`(x, 3), `*`(z)), `-`(`*`(`^`(y, 2), `*`(`^`(z, 2)))))) (1.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[51]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[51]),x,y);
 

{[[0, 1, 0], 2, 2, 2], [[0, 0, 1], 2, 1, 1]} (1.2)
 

> subs(y=t*(x+z),qc[51]);
 

`+`(`*`(`^`(x, 4)), `*`(`^`(x, 3), `*`(z)), `-`(`*`(`^`(t, 2), `*`(`^`(`+`(x, z), 2), `*`(`^`(z, 2)))))) (1.3)
 

> Q51:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q51, `+`(`*`(`^`(U, 4)), `*`(`^`(U, 3)), `-`(`*`(`^`(t, 2), `*`(`^`(U, 2)))), `-`(`*`(2, `*`(`^`(t, 2), `*`(U)))), `-`(`*`(`^`(t, 2))))) (1.4)
 

> subs(U=-1,Q51);
simplify(%);
 

0 (1.5)
 

0 (1.5)
 

> Quartic_to_Weierstrass(Q51,[-1,0]);
 

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

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

`+`(`-`(`*`(3, `*`(X, `*`(`^`(Z, 2))))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`^`(Z, 3))), `*`(`+`(`-`(3), `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z)))), {x = X, y = Y, z = Z}, [x, y, z] (1.7)
 

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

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

> Elliptic_surface(%);
 

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

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

> Show_data();
 

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

Discriminant = `+`(`*`(16, `*`(`^`(t, 4), `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(27)))))) (1.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(256, `*`(`^`(t, 2), `*`(`^`(`+`(`-`(6), `*`(`^`(t, 2))), 3)))), `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(27))))) (1.10)
 

`
` (1.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.51. (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.52 

> qc[52]:=x^4+y^4-x^2*y*z-x*y^2*z;
 

`:=`(qc[52], `+`(`*`(`^`(x, 4)), `*`(`^`(y, 4)), `-`(`*`(`^`(x, 2), `*`(y, `*`(z)))), `-`(`*`(x, `*`(`^`(y, 2), `*`(z)))))) (2.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[52]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[52]),x,y);
 

{[[0, 0, 1], 3, 3, 3]} (2.2)
 

> subs(z=t*(x+y),qc[52]);
 

`+`(`*`(`^`(x, 4)), `*`(`^`(y, 4)), `-`(`*`(`^`(x, 2), `*`(y, `*`(t, `*`(`+`(x, y)))))), `-`(`*`(x, `*`(`^`(y, 2), `*`(t, `*`(`+`(x, y))))))) (2.3)
 

> Q52:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q52, `+`(`*`(`^`(U, 4)), 1, `-`(`*`(`^`(U, 3), `*`(t))), `-`(`*`(2, `*`(`^`(U, 2), `*`(t)))), `-`(`*`(U, `*`(t))))) (2.4)
 

> subs(U=0,Q52);
simplify(%);
 

1 (2.5)
 

1 (2.5)
 

> Quartic_to_Weierstrass(Q52,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(t, `*`(X, `*`(Y, `*`(Z))))), `-`(`*`(t, `*`(`+`(t, 8), `*`(`^`(Z, 3))))), `/`(`*`(t, `*`(`+`(t, 8), `*`(`^`(X, 2), `*`(Z)))), `*`(4)), `*`(4, `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(t, `*`(X, `*`(Y, `*`(Z))))), `-`(`*`(t, `*`(`+`(t, 8), `*`(`^`(Z, 3))))), `/`(`*`(t, `*`(`+`(t, 8), `*`(`^`(X, 2), `*`(Z)))), `*`(4)), `*`(4, `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(t, `*`(X, `*`(Y, `*`(Z))))), `-`(`*`(t, `*`(`+`(t, 8), `*`(`^`(Z, 3))))), `/`(`*`(t, `*`(`+`(t, 8), `*`(`^`(X, 2), `*`(Z)))), `*`(4)), `*`(4, `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(t, `*`(X, `*`(Y, `*`(Z))))), `-`(`*`(t, `*`(`+`(t, 8), `*`(`^`(Z, 3))))), `/`(`*`(t, `*`(`+`(t, 8), `*`(`^`(X, 2), `*`(Z)))), `*`(4)), `*`(4, `...
(2.6)
 

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(128, `*`(t, `*`(`+`(t, 4), `*`(`^`(Z, 3)))))), `*`(8, `*`(`^`(X, 2), `*`(Z, `*`(t)))), `-`(`*`(16, `*`(`+`(t, `-`(2)), `*`(`+`(t, 2), `*`(X, `*...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(128, `*`(t, `*`(`+`(t, 4), `*`(`^`(Z, 3)))))), `*`(8, `*`(`^`(X, 2), `*`(Z, `*`(t)))), `-`(`*`(16, `*`(`+`(t, `-`(2)), `*`(`+`(t, 2), `*`(X, `*...
(2.7)
 

> mapfactor(subs({X=4*X,Y=8*Y},%[1]/64),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(2, `*`(t, `*`(`+`(t, 4), `*`(`^`(Z, 3)))))), `*`(2, `*`(`^`(X, 2), `*`(Z, `*`(t)))), `-`(`*`(`+`(t, `-`(2)), `*`(`+`(t, 2), `*`(X, `*`(`^`(Z, 2... (2.8)
 

> Elliptic_surface(%);
 

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

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(2, `*`(t, `*`(`^`(x, 2))))), `*`(`+`(t, `-`(2)), `*`(`+`(t, 2), `*`(x))), `*`(2, `*`(t, `*`(`+`(t, 4))))) (2.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(2, `*`(t, `*`(`^`(x, 2))))), `*`(`+`(t, `-`(2)), `*`(`+`(t, 2), `*`(x))), `*`(2, `*`(t, `*`(`+`(t, 4))))) (2.10)
 

Discriminant = `+`(`-`(`*`(64, `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(`+`(`*`(`^`(t, 2)), `*`(8, `*`(t)), 8), 2)))))) (2.10)
 

`+`(jay, `-`(invariant)) = `+`(`-`(`/`(`*`(64, `*`(`^`(`+`(`*`(`^`(t, 2)), 12), 3))), `*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`^`(`+`(`*`(`^`(t, 2)), `*`(8, `*`(t)), 8), 2)))))) (2.10)
 

`
` (2.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.52. (2.10)
 

`
` (2.10)
 

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

`
` (2.10)
 

The rank of the Mordell-Weil group over C is 1. (2.10)
 

` ` (2.10)
 

> latex(y^2 = x^3-2*t*x^2+(t-2)*(t+2)*x+2*t*(t+4));
 

{y}^{2}={x}^{3}-2\,t{x}^{2}+ \left( t-2 \right)  \left( t+2 \right) x+
 

2\,t \left( t+4 \right)
 

>
 

Type No. 53 

; 

> qc[53]:=(x^2+y^2-2*x*z)^2-x^2*z^2-y^2*z^2;
 

`:=`(qc[53], `+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(2, `*`(x, `*`(z))))), 2)), `-`(`*`(`^`(x, 2), `*`(`^`(z, 2)))), `-`(`*`(`^`(y, 2), `*`(`^`(z, 2)))))) (3.1)
 

 

 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[53]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[53]),x,y);
 

{[[RootOf(`+`(`*`(`^`(_Z, 2)), 1)), 1, 0], 2, 1, 1], [[0, 0, 1], 2, 1, 2]} (3.2)
 

> subs(z=t*x,qc[53]);
 

`+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(2, `*`(t, `*`(`^`(x, 2)))))), 2)), `-`(`*`(`^`(x, 4), `*`(`^`(t, 2)))), `-`(`*`(`^`(y, 2), `*`(`^`(t, 2), `*`(`^`(x, 2)))))) (3.3)
 

> Q53:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q53, `+`(`-`(`*`(`+`(`-`(2), `*`(4, `*`(t)), `*`(`^`(t, 2))), `*`(`^`(U, 2)))), `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(`^`(U, 4)))), 1)) (3.4)
 

> subs(U=0,Q53);
simplify(%);
 

1 (3.5)
 

1 (3.5)
 

> Quartic_to_Weierstrass(Q53,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(2, `-`(`*`(4, `*`(t))), `-`(`*`(`^`(t, 2)))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(X, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(2, `-`(`*`(4, `*`(t))), `-`(`*`(`^`(t, 2)))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(X, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(2, `-`(`*`(4, `*`(t))), `-`(`*`(`^`(t, 2)))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(X, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(2, `-`(`*`(4, `*`(t))), `-`(`*`(`^`(t, 2)))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(X, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(2, `-`(`*`(4, `*`(t))), `-`(`*`(`^`(t, 2)))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(X, ...
(3.6)
 

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

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

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(`+`(`-`(2), `*`(4, `*`(t)), `*`(`^`(t, 2))), `*`(`^`(Z, 3))))))), `*`(4, `*`(`+`(`*...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(`+`(`-`(2), `*`(4, `*`(t)), `*`(`^`(t, 2))), `*`(`^`(Z, 3))))))), `*`(4, `*`(`+`(`*...
(3.8)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (3.9)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(2, `-`(`*`(4, `*`(t))), `-`(`*`(`^`(t, 2)))), `*`(`^`(x, 2))), `-`(`*`(4, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(x))))), `*`(4, `*`(`+`(`... (3.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(2, `-`(`*`(4, `*`(t))), `-`(`*`(`^`(t, 2)))), `*`(`^`(x, 2))), `-`(`*`(4, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(x))))), `*`(4, `*`(`+`(`... (3.10)
 

Discriminant = `+`(`*`(256, `*`(`^`(t, 6), `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`+`(t, `-`(1)), `*`(`^`(`+`(t, 8), 2))))))) (3.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(16, `-`(`*`(64, `*`(t))), `*`(48, `*`(`^`(t, 2))), `*`(8, `*`(`^`(t, 3))), `*`(`^`(t, 4))), 3))), `*`(`^`(t, 6), `*`(`+`(`*`(3, `*`(t)), `-`(1)),... (3.10)
 

`
` (3.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.53. (3.10)
 

`
` (3.10)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (3.10)
 

`
` (3.10)
 

The rank of the Mordell-Weil group over C is 1. (3.10)
 

` ` (3.10)
 

>
 

TypeNo.54 

> qc[54]:=(x^2-y*z)*(x^2+y*z);
 

`:=`(qc[54], `*`(`+`(`*`(`^`(x, 2)), `-`(`*`(y, `*`(z)))), `*`(`+`(`*`(`^`(x, 2)), `*`(y, `*`(z)))))) (4.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[54]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[54]),x,y);
 

{[[0, 0, 1], 2, 2, 2], [[0, 1, 0], 2, 2, 2]} (4.2)
 

> subs(y=t*(x-z),qc[54]);
 

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

> Q54:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q54, `+`(`*`(`^`(U, 4)), `-`(`*`(`^`(t, 2), `*`(`^`(U, 2)))), `*`(2, `*`(`^`(t, 2), `*`(U))), `-`(`*`(`^`(t, 2))))) (4.4)
 

> subs(U=1,Q54);
simplify(%);
 

1 (4.5)
 

1 (4.5)
 

> Quartic_to_Weierstrass(Q54,[1,1]);
 

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

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(`+`(`-`(6), `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z))), `-`(`*`(12, `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(4, `*`(`+`(2, `*`(`^`(t, 2))), `*`(`^`(Z, 3))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(`+`(`-`(6), `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z))), `-`(`*`(12, `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(4, `*`(`+`(2, `*`(`^`(t, 2))), `*`(`^`(Z, 3))))...
(4.7)
 

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(`+`(`-`(6), `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z))), `-`(`*`(12, `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(4, `*`(`+`(2, `*`(`^`(t, 2))), `*`(`^`(Z, 3))))... (4.8)
 

> Elliptic_surface(%);
 

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

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

> Show_data();
 

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

Discriminant = `+`(`*`(256, `*`(`^`(t, 6), `*`(`+`(t, `-`(4)), `*`(`+`(t, 4)))))) (4.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(`-`(12), `*`(`^`(t, 2))), 3))), `*`(`+`(t, `-`(4)), `*`(`+`(t, 4))))) (4.10)
 

`
` (4.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.54. (4.10)
 

`
` (4.10)
 

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

`
` (4.10)
 

The rank of the Mordell-Weil group over C is 1. (4.10)
 

` ` (4.10)
 

>
 

 

TypeNo.55 

> qc[55]:=(x^2-y*z)^2-x^3*y;
 

`:=`(qc[55], `+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `-`(`*`(y, `*`(z)))), 2)), `-`(`*`(`^`(x, 3), `*`(y))))) (5.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[55]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[55]),x,y);
 

{[[0, 0, 1], 2, 2, 1], [[0, 1, 0], 2, 1, 1]} (5.2)
 

> subs(y=t*(x+4*z)-4*z,qc[55]);
 

`+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `-`(`*`(`+`(`*`(t, `*`(`+`(x, `*`(4, `*`(z))))), `-`(`*`(4, `*`(z)))), `*`(z)))), 2)), `-`(`*`(`^`(x, 3), `*`(`+`(`*`(t, `*`(`+`(x, `*`(4, `*`(z))))), `-`(`*`(4, `*`(z)... (5.3)
 

> Q55:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q55, `+`(`*`(8, `*`(t, `*`(`+`(t, `-`(1)), `*`(U)))), `-`(`*`(2, `*`(`+`(`-`(2), `*`(3, `*`(t))), `*`(`^`(U, 3))))), `-`(`*`(`+`(t, `-`(1)), `*`(`^`(U, 4)))), `*`(`+`(`-`(`*`(8, `*`(t))), 8, `*`(...
`:=`(Q55, `+`(`*`(8, `*`(t, `*`(`+`(t, `-`(1)), `*`(U)))), `-`(`*`(2, `*`(`+`(`-`(2), `*`(3, `*`(t))), `*`(`^`(U, 3))))), `-`(`*`(`+`(t, `-`(1)), `*`(`^`(U, 4)))), `*`(`+`(`-`(`*`(8, `*`(t))), 8, `*`(...
(5.4)
 

> subs(U=-4,Q55);
simplify(%);
 

`+`(`-`(`*`(32, `*`(t, `*`(`+`(t, `-`(1)))))), 128, `*`(16, `*`(`^`(t, 2))), `*`(16, `*`(`^`(`+`(t, `-`(1)), 2)))) (5.5)
 

144 (5.5)
 

> Quartic_to_Weierstrass(Q55,[-4,12]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(24, `*`(t)), `-`(128)), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`*`(414720, `*`(t)), `-`(497664)), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(30...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(24, `*`(t)), `-`(128)), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`*`(414720, `*`(t)), `-`(497664)), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(30...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(24, `*`(t)), `-`(128)), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`*`(414720, `*`(t)), `-`(497664)), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(30...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(24, `*`(t)), `-`(128)), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`*`(414720, `*`(t)), `-`(497664)), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(30...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(24, `*`(t)), `-`(128)), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`*`(414720, `*`(t)), `-`(497664)), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(30...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(24, `*`(t)), `-`(128)), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`*`(414720, `*`(t)), `-`(497664)), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(30...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(24, `*`(t)), `-`(128)), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`*`(414720, `*`(t)), `-`(497664)), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(30...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(24, `*`(t)), `-`(128)), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`*`(414720, `*`(t)), `-`(497664)), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(30...
(5.6)
 

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(144, `*`(`+`(`-`(`*`(32, `*`(t))), 56, `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(191102976, `*`(`+`(`-`(`*`(100, `*`(t))), `*`(33, `*...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(144, `*`(`+`(`-`(`*`(32, `*`(t))), 56, `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(191102976, `*`(`+`(`-`(`*`(100, `*`(t))), `*`(33, `*...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(144, `*`(`+`(`-`(`*`(32, `*`(t))), 56, `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(191102976, `*`(`+`(`-`(`*`(100, `*`(t))), `*`(33, `*...
(5.7)
 

> mapfactor(subs({X=4*9*X,Y=27*8*Y},%[1]/(27^2*8^2)),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`+`(`-`(`*`(32, `*`(t))), 56, `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(4096, `*`(`+`(`-`(`*`(100, `*`(t))), `*`(33, `*`(`^`(t...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`+`(`-`(`*`(32, `*`(t))), 56, `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(4096, `*`(`+`(`-`(`*`(100, `*`(t))), `*`(33, `*`(`^`(t...
(5.8)
 

> mapfactor(subs({X=4*X,Y=8*Y},%/64),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(32, `*`(t))), 56, `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(64, `*`(`+`(`-`(`*`(100, `*`(t))), `*`(33, `*`(`^`(t, 2))), 76...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(32, `*`(t))), 56, `*`(`^`(t, 2))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(64, `*`(`+`(`-`(`*`(100, `*`(t))), `*`(33, `*`(`^`(t, 2))), 76...
(5.9)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (5.10)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(32, `*`(t))), 56, `*`(`^`(t, 2))), `*`(`^`(x, 2))), `*`(`+`(`-`(`*`(992, `*`(t))), 960, `*`(240, `*`(`^`(t, 2)))), `*`(x)), 4864, `-`(`*`(6400, `*`... (5.10)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(32, `*`(t))), 56, `*`(`^`(t, 2))), `*`(`^`(x, 2))), `*`(`+`(`-`(`*`(992, `*`(t))), 960, `*`(240, `*`(`^`(t, 2)))), `*`(x)), 4864, `-`(`*`(6400, `*`... (5.11)
 

Discriminant = `+`(`*`(262144, `*`(`+`(`*`(3, `*`(`^`(t, 3))), `-`(`*`(188, `*`(`^`(t, 2)))), `*`(332, `*`(t)), `-`(148)), `*`(`^`(`+`(t, `-`(1)), 5))))) (5.11)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(`^`(`+`(256, `-`(`*`(608, `*`(t))), `*`(416, `*`(`^`(t, 2))), `-`(`*`(64, `*`(`^`(t, 3)))), `*`(`^`(t, 4))), 3)), `*`(64, `*`(`+`(`*`(3, `*`(`^`(t, 3))), `-`(`*`... (5.11)
 

`
` (5.11)
 

This is a rational elliptic surface; Oguiso-Shioda type No.55. (5.11)
 

`
` (5.11)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (5.11)
 

`
` (5.11)
 

The rank of the Mordell-Weil group over C is 1. (5.11)
 

` ` (5.11)
 

>
 

TypeNo.56 

> qc[56]:=(x^2-y*z)^2-x^3*y;
 

`:=`(qc[56], `+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `-`(`*`(y, `*`(z)))), 2)), `-`(`*`(`^`(x, 3), `*`(y))))) (6.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[56]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[56]),x,y);
 

{[[0, 0, 1], 2, 2, 1], [[0, 1, 0], 2, 1, 1]} (6.2)
 

> subs(z=t*(x-y),qc[56]);
 

`+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `-`(`*`(y, `*`(t, `*`(`+`(x, `-`(y))))))), 2)), `-`(`*`(`^`(x, 3), `*`(y)))) (6.3)
 

> Q56:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q56, `+`(`-`(`*`(2, `*`(`^`(t, 2), `*`(U)))), `-`(`*`(`+`(`*`(2, `*`(t)), 1), `*`(`^`(U, 3)))), `*`(`^`(U, 4)), `*`(t, `*`(`+`(t, 2), `*`(`^`(U, 2)))), `*`(`^`(t, 2)))) (6.4)
 

> subs(U=1,Q56);
simplify(%);
 

`+`(`-`(`*`(`^`(t, 2))), `-`(`*`(2, `*`(t))), `*`(t, `*`(`+`(t, 2)))) (6.5)
 

0 (6.5)
 

> Quartic_to_Weierstrass(Q56,[1,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(t, `-`(1)), `*`(`+`(t, `-`(3)), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`+`(`*`(2, `*`(t)), `-`(3)), `*`(X, `*`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(t, `-`(1)), `*`(`+`(t, `-`(3)), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`+`(`*`(2, `*`(t)), `-`(3)), `*`(X, `*`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(t, `-`(1)), `*`(`+`(t, `-`(3)), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(`+`(`*`(2, `*`(t)), `-`(1)), `*`(`+`(`*`(2, `*`(t)), `-`(3)), `*`(X, `*`...
(6.6)
 

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

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

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

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

> Elliptic_surface(%);
 

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

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

> Show_data();
 

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

Discriminant = `+`(`*`(16, `*`(`^`(t, 4), `*`(`+`(`*`(4, `*`(t)), `-`(27)), `*`(`^`(`+`(`*`(2, `*`(t)), `-`(1)), 2)))))) (6.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(256, `*`(`^`(t, 2), `*`(`^`(`+`(`*`(`^`(t, 2)), `-`(`*`(8, `*`(t))), 10), 3)))), `*`(`+`(`*`(4, `*`(t)), `-`(27)), `*`(`^`(`+`(`*`(2, `*`(t)), `-`(1)), 2))))) (6.10)
 

`
` (6.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.56. (6.10)
 

`
` (6.10)
 

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

`
` (6.10)
 

The rank of the Mordell-Weil group over C is 1. (6.10)
 

` ` (6.10)
 

>
 

TypeNo.57 

> qc[57]:=(x^2+y^2-3*x*z)^2-4*x^2*(2*z^2-x*z);
 

`:=`(qc[57], `+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(3, `*`(x, `*`(z))))), 2)), `-`(`*`(4, `*`(`^`(x, 2), `*`(`+`(`*`(2, `*`(`^`(z, 2))), `-`(`*`(x, `*`(z)))))))))) (7.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[57]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[57]),x,y);
 

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

> subs(z=t*x,qc[57]);
 

`+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(3, `*`(t, `*`(`^`(x, 2)))))), 2)), `-`(`*`(4, `*`(`^`(x, 2), `*`(`+`(`*`(2, `*`(`^`(t, 2), `*`(`^`(x, 2)))), `-`(`*`(t, `*`(`^`(x, 2)))))))))) (7.3)
 

> Q57:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q57, `+`(`-`(`*`(2, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`^`(U, 2))))), `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(U, 4))), 1)) (7.4)
 

> subs(U=0,Q57);
simplify(%);
 

1 (7.5)
 

1 (7.5)
 

> Quartic_to_Weierstrass(Q57,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(2, `-`(`*`(6, `*`(t)))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`^`(`+`(t, `-`(1)), 2), `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(8, `*`(`+`(`*`(3, `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(2, `-`(`*`(6, `*`(t)))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`^`(`+`(t, `-`(1)), 2), `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(8, `*`(`+`(`*`(3, `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(2, `-`(`*`(6, `*`(t)))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`^`(`+`(t, `-`(1)), 2), `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(8, `*`(`+`(`*`(3, `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(2, `-`(`*`(6, `*`(t)))), `*`(`^`(X, 2), `*`(Z)))), `*`(4, `*`(`^`(`+`(t, `-`(1)), 2), `*`(X, `*`(`^`(Z, 2))))), `-`(`*`(8, `*`(`+`(`*`(3, `...
(7.6)
 

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(8, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(Z, 3)))))), `*`(4, `*`(`^`(`+`(t, `-`(1)), 2), `*`(X, `*`(`^`(Z, 2)))))...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(8, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(Z, 3)))))), `*`(4, `*`(`^`(`+`(t, `-`(1)), 2), `*`(X, `*`(`^`(Z, 2)))))...
(7.7)
 

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(8, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`^`(`+`(t, `-`(1)), 2), `*`(`^`(Z, 3)))))), `*`(4, `*`(`^`(`+`(t, `-`(1)), 2), `*`(X, `*`(`^`(Z, 2)))))... (7.8)
 

> Elliptic_surface(%);
 

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

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(2, `-`(`*`(6, `*`(t)))), `*`(`^`(x, 2))), `-`(`*`(4, `*`(`^`(`+`(t, `-`(1)), 2), `*`(x)))), `*`(8, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`^`(`+`(t, `-`(1)),... (7.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(2, `-`(`*`(6, `*`(t)))), `*`(`^`(x, 2))), `-`(`*`(4, `*`(`^`(`+`(t, `-`(1)), 2), `*`(x)))), `*`(8, `*`(`+`(`*`(3, `*`(t)), `-`(1)), `*`(`^`(`+`(t, `-`(1)),... (7.10)
 

Discriminant = `+`(`*`(65536, `*`(`^`(t, 2), `*`(`^`(`+`(`*`(2, `*`(t)), `-`(1)), 2), `*`(`^`(`+`(t, `-`(1)), 2)))))) (7.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(256, `*`(`^`(`+`(1, `-`(`*`(3, `*`(t))), `*`(3, `*`(`^`(t, 2)))), 3))), `*`(`^`(t, 2), `*`(`^`(`+`(`*`(2, `*`(t)), `-`(1)), 2), `*`(`^`(`+`(t, `-`(1)), 2)))))) (7.10)
 

`
` (7.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.57. (7.10)
 

`
` (7.10)
 

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

`
` (7.10)
 

The rank of the Mordell-Weil group over C is 1. (7.10)
 

` ` (7.10)
 

>
 

TypeNo.58 

> qc[58]:=(x^2+y^2-z^2)*(4*x^2+y^2-4*z^2);
 

`:=`(qc[58], `*`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(`^`(z, 2)))), `*`(`+`(`*`(4, `*`(`^`(x, 2))), `*`(`^`(y, 2)), `-`(`*`(4, `*`(`^`(z, 2)))))))) (8.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[58]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[58]),x,y);
 

{[[-1, 0, 1], 2, 2, 2], [[1, 0, 1], 2, 2, 2]} (8.2)
 

> subs(y=t*x+z,qc[58]);
 

`*`(`+`(`*`(`^`(x, 2)), `*`(`^`(`+`(`*`(t, `*`(x)), z), 2)), `-`(`*`(`^`(z, 2)))), `*`(`+`(`*`(4, `*`(`^`(x, 2))), `*`(`^`(`+`(`*`(t, `*`(x)), z), 2)), `-`(`*`(4, `*`(`^`(z, 2))))))) (8.3)
 

> Q58:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q58, `+`(`*`(`+`(1, `*`(`^`(t, 2))), `*`(`+`(4, `*`(`^`(t, 2))), `*`(`^`(U, 4)))), `*`(2, `*`(t, `*`(`+`(5, `*`(2, `*`(`^`(t, 2)))), `*`(`^`(U, 3))))), `*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(U,... (8.4)
 

> subs(U=0,Q58);
simplify(%);
 

0 (8.5)
 

0 (8.5)
 

> Quartic_to_Weierstrass(Q58,[0,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(36, `*`(`^`(t, 2), `*`(`+`(1, `*`(`^`(t, 2))), `*`(`+`(4, `*`(`^`(t, 2))), `*`(`^`(Z, 3))))))), `-`(`*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(X,...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(36, `*`(`^`(t, 2), `*`(`+`(1, `*`(`^`(t, 2))), `*`(`+`(4, `*`(`^`(t, 2))), `*`(`^`(Z, 3))))))), `-`(`*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(X,...
(8.6)
 

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(36, `*`(`^`(t, 2), `*`(`+`(1, `*`(`^`(t, 2))), `*`(`+`(4, `*`(`^`(t, 2))), `*`(`^`(Z, 3))))))), `-`(`*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(X,...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(36, `*`(`^`(t, 2), `*`(`+`(1, `*`(`^`(t, 2))), `*`(`+`(4, `*`(`^`(t, 2))), `*`(`^`(Z, 3))))))), `-`(`*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(X,...
(8.7)
 

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(36, `*`(`^`(t, 2), `*`(`+`(1, `*`(`^`(t, 2))), `*`(`+`(4, `*`(`^`(t, 2))), `*`(`^`(Z, 3))))))), `-`(`*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(X,... (8.8)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (8.9)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(x, 2))), `-`(`*`(12, `*`(`^`(t, 2), `*`(`+`(5, `*`(2, `*`(`^`(t, 2)))), `*`(x))))), `*`(36, `*`(`^`(t, 2), `*`(`+`(1, `*`(... (8.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`*`(`^`(t, 2)), `-`(3)), `*`(`^`(x, 2))), `-`(`*`(12, `*`(`^`(t, 2), `*`(`+`(5, `*`(2, `*`(`^`(t, 2)))), `*`(x))))), `*`(36, `*`(`^`(t, 2), `*`(`+`(1, `*`(... (8.10)
 

Discriminant = `+`(`*`(82944, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 3), `*`(`^`(`+`(t, `-`(1)), 4), `*`(`^`(`+`(t, 1), 4))))))) (8.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(4, `*`(`^`(`+`(9, `*`(174, `*`(`^`(t, 2))), `*`(73, `*`(`^`(t, 4)))), 3))), `*`(81, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 2)), 3), `*`(`^`(`+`(t, `-`(1)), 4), `*`(`^... (8.10)
 

`
` (8.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.58. (8.10)
 

`
` (8.10)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (8.10)
 

`
` (8.10)
 

The rank of the Mordell-Weil group over C is 1. (8.10)
 

` ` (8.10)
 

>
 

TypeNo.59 

> qc[59]:=(x^2+4*y^2-4*z^2)*(x^2+(y-z)^2-4*z^2);
 

`:=`(qc[59], `*`(`+`(`*`(`^`(x, 2)), `*`(4, `*`(`^`(y, 2))), `-`(`*`(4, `*`(`^`(z, 2))))), `*`(`+`(`*`(`^`(x, 2)), `*`(`^`(`+`(y, `-`(z)), 2)), `-`(`*`(4, `*`(`^`(z, 2)))))))) (9.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[59]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[59]),x,y);
 

{[[RootOf(`+`(`*`(9, `*`(`^`(_Z, 2))), `-`(32))), `/`(1, 3), 1], 2, 1, 2], [[0, -1, 1], 2, 2, 2]} (9.2)
 

> subs(y=t*(x-2*z)+z,qc[59]);
 

`*`(`+`(`*`(`^`(x, 2)), `*`(4, `*`(`^`(`+`(`*`(t, `*`(`+`(x, `-`(`*`(2, `*`(z)))))), z), 2))), `-`(`*`(4, `*`(`^`(z, 2))))), `*`(`+`(`*`(`^`(x, 2)), `*`(`^`(t, 2), `*`(`^`(`+`(x, `-`(`*`(2, `*`(z)))),... (9.3)
 

> Q59:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q59, `+`(`-`(`*`(32, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(`*`(4, `*`(`^`(t, 2))), t, `-`(1)), `*`(U)))))), `-`(`*`(4, `*`(t, `*`(`+`(`*`(8, `*`(`^`(t, 3))), `*`(5, `*`(t)), `-`(`*`(2, `*`(`^`(t, 2)...
`:=`(Q59, `+`(`-`(`*`(32, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(`*`(4, `*`(`^`(t, 2))), t, `-`(1)), `*`(U)))))), `-`(`*`(4, `*`(t, `*`(`+`(`*`(8, `*`(`^`(t, 3))), `*`(5, `*`(t)), `-`(`*`(2, `*`(`^`(t, 2)...
(9.4)
 

> subs(U=2,Q59);
simplify(%);
 

`+`(`-`(`*`(64, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(`*`(4, `*`(`^`(t, 2))), t, `-`(1))))))), `-`(`*`(32, `*`(t, `*`(`+`(`*`(8, `*`(`^`(t, 3))), `*`(5, `*`(t)), `-`(`*`(2, `*`(`^`(t, 2)))), `-`(2)))))),...
`+`(`-`(`*`(64, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(`*`(4, `*`(`^`(t, 2))), t, `-`(1))))))), `-`(`*`(32, `*`(t, `*`(`+`(`*`(8, `*`(`^`(t, 3))), `*`(5, `*`(t)), `-`(`*`(2, `*`(`^`(t, 2)))), `-`(2)))))),...
(9.5)
 

0 (9.5)
 

> Quartic_to_Weierstrass(Q59,[2,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(4, `*`(`^`(t, 2))), `*`(32, `*`(t)), 20), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`*`(320, `*`(`^`(t, 2))), `*`(128, `*`(`^`(t, 3))), `*`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(4, `*`(`^`(t, 2))), `*`(32, `*`(t)), 20), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`*`(320, `*`(`^`(t, 2))), `*`(128, `*`(`^`(t, 3))), `*`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(4, `*`(`^`(t, 2))), `*`(32, `*`(t)), 20), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`*`(320, `*`(`^`(t, 2))), `*`(128, `*`(`^`(t, 3))), `*`...
(9.6)
 

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`+`(`*`(`^`(t, 2)), `*`(8, `*`(t)), 5), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(64, `*`(`+`(`*`(5, `*`(`^`(t, 2))), `*`(2, `*`(`^`(t, 3))), `...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(4, `*`(`+`(`*`(`^`(t, 2)), `*`(8, `*`(t)), 5), `*`(`^`(X, 2), `*`(Z))))), `-`(`*`(64, `*`(`+`(`*`(5, `*`(`^`(t, 2))), `*`(2, `*`(`^`(t, 3))), `...
(9.7)
 

> mapfactor(subs({X=4*X,Y=8*Y},%[1]/64),[X,Y]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(`^`(t, 2)), `*`(8, `*`(t)), 5), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(4, `*`(`+`(`*`(5, `*`(`^`(t, 2))), `*`(2, `*`(`^`(t, 3))), `*`(2, `*`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(`^`(t, 2)), `*`(8, `*`(t)), 5), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(4, `*`(`+`(`*`(5, `*`(`^`(t, 2))), `*`(2, `*`(`^`(t, 3))), `*`(2, `*`...
(9.8)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (9.9)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`*`(`^`(t, 2)), `*`(8, `*`(t)), 5), `*`(`^`(x, 2))), `*`(`+`(`*`(20, `*`(`^`(t, 2))), `*`(8, `*`(`^`(t, 3))), `*`(8, `*`(t)), 8), `*`(x)), `*`(4, `*`(`+`(1... (9.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`*`(`^`(t, 2)), `*`(8, `*`(t)), 5), `*`(`^`(x, 2))), `*`(`+`(`*`(20, `*`(`^`(t, 2))), `*`(8, `*`(`^`(t, 3))), `*`(8, `*`(t)), 8), `*`(x)), `*`(4, `*`(`+`(1... (9.10)
 

Discriminant = `+`(`*`(1024, `*`(t, `*`(`^`(`+`(`*`(`^`(t, 2)), `-`(`*`(6, `*`(t))), 1), 2), `*`(`^`(`+`(t, `-`(1)), 4)))))) (9.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(4, `*`(`^`(`+`(`*`(`^`(t, 4)), `-`(`*`(8, `*`(`^`(t, 3)))), `*`(14, `*`(`^`(t, 2))), `*`(56, `*`(t)), 1), 3))), `*`(t, `*`(`^`(`+`(`*`(`^`(t, 2)), `-`(`*`(6, `*`... (9.10)
 

`
` (9.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.59. (9.10)
 

`
` (9.10)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (9.10)
 

`
` (9.10)
 

The rank of the Mordell-Weil group over C is 1. (9.10)
 

` ` (9.10)
 

>
 

TypeNo.60 

> qc[60]:=x^4+y^4-x^2*z^2;
 

`:=`(qc[60], `+`(`*`(`^`(x, 4)), `*`(`^`(y, 4)), `-`(`*`(`^`(x, 2), `*`(`^`(z, 2)))))) (10.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[60]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[60]),x,y);
 

{[[0, 0, 1], 2, 2, 2]} (10.2)
 

> subs(z=t*y,qc[60]);
 

`+`(`*`(`^`(x, 4)), `*`(`^`(y, 4)), `-`(`*`(`^`(x, 2), `*`(`^`(t, 2), `*`(`^`(y, 2)))))) (10.3)
 

> Q60:=mapfactor(subs({x=1,y=U},%),U);
 

`:=`(Q60, `+`(1, `*`(`^`(U, 4)), `-`(`*`(`^`(t, 2), `*`(`^`(U, 2)))))) (10.4)
 

> subs(U=0,Q60);
simplify(%);
 

1 (10.5)
 

1 (10.5)
 

> Quartic_to_Weierstrass(Q60,[0,1]);
 

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

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(`^`(t, 2), `*`(`^`(X, 2), `*`(Z))), `*`(4, `*`(X, `*`(`^`(Z, 2)))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`^`(Z, 3)))))), {x = X, y = Y, z = Z}, [x, y, z] (10.7)
 

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

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

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (10.9)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(`^`(t, 2), `*`(`^`(x, 2)))), `-`(`*`(4, `*`(x))), `*`(4, `*`(`^`(t, 2)))) (10.9)
 

> Show_data();
 

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

Discriminant = `+`(`*`(256, `*`(`^`(`+`(`*`(`^`(t, 2)), `-`(2)), 2), `*`(`^`(`+`(`*`(`^`(t, 2)), 2), 2))))) (10.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(`*`(`^`(t, 4)), 12), 3))), `*`(`^`(`+`(`*`(`^`(t, 2)), `-`(2)), 2), `*`(`^`(`+`(`*`(`^`(t, 2)), 2), 2))))) (10.10)
 

`
` (10.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.60. (10.10)
 

`
` (10.10)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (10.10)
 

`
` (10.10)
 

The rank of the Mordell-Weil group over C is 1. (10.10)
 

` ` (10.10)
 

>