Type21-30.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.21 

> qc[21]:=(2*x^2-z^2+2*y^2)^2-4*x*y*(x-y)^2;
 

`:=`(qc[21], `+`(`*`(`^`(`+`(`*`(2, `*`(`^`(x, 2))), `-`(`*`(`^`(z, 2))), `*`(2, `*`(`^`(y, 2)))), 2)), `-`(`*`(4, `*`(x, `*`(y, `*`(`^`(`+`(x, `-`(y)), 2)))))))) (1.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[21]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[21]),x,y);
 

{[[`/`(1, 2), `/`(1, 2), 1], 2, 1, 2], [[-`/`(1, 2), -`/`(1, 2), 1], 2, 1, 2]} (1.2)
 

> subs(y=t*x,qc[21]);
 

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

> Q21:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q21, `+`(`-`(`*`(4, `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(U, 2))))), `*`(4, `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(`^`(U, 4)))), 1)) (1.4)
 

> subs(U=0,Q21);
simplify(%);
 

1 (1.5)
 

1 (1.5)
 

> Quartic_to_Weierstrass(Q21,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(4), `-`(`*`(4, `*`(`^`(t, 2))))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`-`(16), `-`(`*`(64, `*`(`^`(t, 2)))), `-`(`*`(16, `*`(`^`(t, 4...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(4), `-`(`*`(4, `*`(`^`(t, 2))))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`-`(16), `-`(`*`(64, `*`(`^`(t, 2)))), `-`(`*`(16, `*`(`^`(t, 4...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(4), `-`(`*`(4, `*`(`^`(t, 2))))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`-`(16), `-`(`*`(64, `*`(`^`(t, 2)))), `-`(`*`(16, `*`(`^`(t, 4...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(4), `-`(`*`(4, `*`(`^`(t, 2))))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`-`(16), `-`(`*`(64, `*`(`^`(t, 2)))), `-`(`*`(16, `*`(`^`(t, 4...
(1.6)
 

`+`(`*`(`^`(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), `...
(1.7)
 

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

`+`(`*`(`^`(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), `...
(1.8)
 

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

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2)))), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(X, 2), `*...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(X, `*`(`^`(Z, 2)))), `*`(`+`(`*`(`^`(t, 2)), 1), `*`(`^`(X, 2), `*...
(1.9)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (1.10)
 

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

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(`^`(t, 2))), `-`(1)), `*`(`^`(x, 2))), `*`(`+`(`-`(`*`(`^`(t, 4))), `*`(`^`(t, 3)), `-`(`*`(4, `*`(`^`(t, 2)))), t, `-`(1)), `*`(x)), `*`(`+`(`*`(`... (1.11)
 

Discriminant = `+`(`*`(64, `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 4)), `-`(`*`(`^`(t, 3))), `*`(4, `*`(`^`(t, 2))), `-`(t), 1), `*`(`^`(`+`(t, `-`(1)), 4)))))) (1.11)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(64, `*`(`^`(`+`(4, `*`(14, `*`(`^`(t, 2))), `*`(4, `*`(`^`(t, 4))), `-`(`*`(3, `*`(`^`(t, 3)))), `-`(`*`(3, `*`(t)))), 3))), `*`(`^`(t, 2), `*`(`+`(`*`(`^`(t, 4)... (1.11)
 

`
` (1.11)
 

This is a rational elliptic surface; Oguiso-Shioda type No.21. (1.11)
 

`
` (1.11)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (1.11)
 

`
` (1.11)
 

The rank of the Mordell-Weil group over C is 3. (1.11)
 

` ` (1.11)
 

TypeNo.22 

> qc[22]:=2*x^4+y^4-3*x^2*y*z-2*y^3*z+y^2*z^2;
 

`:=`(qc[22], `+`(`*`(2, `*`(`^`(x, 4))), `*`(`^`(y, 4)), `-`(`*`(3, `*`(`^`(x, 2), `*`(y, `*`(z))))), `-`(`*`(2, `*`(`^`(y, 3), `*`(z)))), `*`(`^`(y, 2), `*`(`^`(z, 2))))) (2.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[22]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[22]),x,y);
 

{[[0, 1, 1], 2, 1, 2], [[0, 0, 1], 2, 2, 2]} (2.2)
 

> subs(y=t*(x-z)+2*z,qc[22]);
 

`+`(`*`(2, `*`(`^`(x, 4))), `*`(`^`(`+`(`*`(t, `*`(`+`(x, `-`(z)))), `*`(2, `*`(z))), 4)), `-`(`*`(3, `*`(`^`(x, 2), `*`(`+`(`*`(t, `*`(`+`(x, `-`(z)))), `*`(2, `*`(z))), `*`(z))))), `-`(`*`(2, `*`(`^...
`+`(`*`(2, `*`(`^`(x, 4))), `*`(`^`(`+`(`*`(t, `*`(`+`(x, `-`(z)))), `*`(2, `*`(z))), 4)), `-`(`*`(3, `*`(`^`(x, 2), `*`(`+`(`*`(t, `*`(`+`(x, `-`(z)))), `*`(2, `*`(z))), `*`(z))))), `-`(`*`(2, `*`(`^...
(2.3)
 

> Q22:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q22, `+`(`-`(`*`(2, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(`-`(2), t), `*`(`+`(`*`(2, `*`(t)), `-`(3)), `*`(U))))))), `*`(`+`(`*`(`^`(t, 4)), 2), `*`(`^`(U, 4))), `-`(`*`(t, `*`(`+`(3, `-`(`*`(6, `*`...
`:=`(Q22, `+`(`-`(`*`(2, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(`-`(2), t), `*`(`+`(`*`(2, `*`(t)), `-`(3)), `*`(U))))))), `*`(`+`(`*`(`^`(t, 4)), 2), `*`(`^`(U, 4))), `-`(`*`(t, `*`(`+`(3, `-`(`*`(6, `*`...
(2.4)
 

> subs(U=1,Q22);
simplify(%);
 

`+`(`-`(`*`(2, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(`-`(2), t), `*`(`+`(`*`(2, `*`(t)), `-`(3)))))))), `*`(7, `*`(`^`(t, 4))), `-`(4), `-`(`*`(t, `*`(`+`(3, `-`(`*`(6, `*`(`^`(t, 2)))), `*`(4, `*`(`^`(t...
`+`(`-`(`*`(2, `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(`-`(2), t), `*`(`+`(`*`(2, `*`(t)), `-`(3)))))))), `*`(7, `*`(`^`(t, 4))), `-`(4), `-`(`*`(t, `*`(`+`(3, `-`(`*`(6, `*`(`^`(t, 2)))), `*`(4, `*`(`^`(t...
(2.5)
 

0 (2.5)
 

> Quartic_to_Weierstrass(Q22,[1,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(6, `*`(t))), 6, `*`(13, `*`(`^`(t, 2)))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`-`(`*`(3, `*`(t))), `*`(6, `*`(`^`(t, 3))), 8), `*...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(6, `*`(t))), 6, `*`(13, `*`(`^`(t, 2)))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`-`(`*`(3, `*`(t))), `*`(6, `*`(`^`(t, 3))), 8), `*...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(6, `*`(t))), 6, `*`(13, `*`(`^`(t, 2)))), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(`+`(`-`(`*`(3, `*`(t))), `*`(6, `*`(`^`(t, 3))), 8), `*...
(2.6)
 

>
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (2.7)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(6, `*`(t))), 6, `*`(13, `*`(`^`(t, 2)))), `*`(`^`(x, 2))), `*`(`+`(`-`(4), `*`(9, `*`(t))), `*`(`+`(`-`(`*`(3, `*`(t))), `*`(6, `*`(`^`(t, 3))), 8)...
`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(6, `*`(t))), 6, `*`(13, `*`(`^`(t, 2)))), `*`(`^`(x, 2))), `*`(`+`(`-`(4), `*`(9, `*`(t))), `*`(`+`(`-`(`*`(3, `*`(t))), `*`(6, `*`(`^`(t, 3))), 8)...
(2.7)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(6, `*`(t))), 6, `*`(13, `*`(`^`(t, 2)))), `*`(`^`(x, 2))), `*`(`+`(`-`(4), `*`(9, `*`(t))), `*`(`+`(`-`(`*`(3, `*`(t))), `*`(6, `*`(`^`(t, 3))), 8)...
`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(6, `*`(t))), 6, `*`(13, `*`(`^`(t, 2)))), `*`(`^`(x, 2))), `*`(`+`(`-`(4), `*`(9, `*`(t))), `*`(`+`(`-`(`*`(3, `*`(t))), `*`(6, `*`(`^`(t, 3))), 8)...
(2.8)
 

Discriminant = `+`(`-`(`*`(16, `*`(`+`(`*`(31, `*`(`^`(t, 4))), `-`(`*`(194, `*`(`^`(t, 3)))), `*`(407, `*`(`^`(t, 2))), `-`(`*`(284, `*`(t))), `-`(8)), `*`(`^`(`+`(`-`(4), `*`(9, `*`(t))), 2), `*`(`^... (2.8)
 

`+`(jay, `-`(invariant)) = `+`(`-`(`/`(`*`(256, `*`(`^`(`+`(132, `-`(`*`(324, `*`(t))), `*`(273, `*`(`^`(t, 2))), `-`(`*`(84, `*`(`^`(t, 3)))), `*`(7, `*`(`^`(t, 4)))), 3))), `*`(`+`(`*`(31, `*`(`^`(t...
`+`(jay, `-`(invariant)) = `+`(`-`(`/`(`*`(256, `*`(`^`(`+`(132, `-`(`*`(324, `*`(t))), `*`(273, `*`(`^`(t, 2))), `-`(`*`(84, `*`(`^`(t, 3)))), `*`(7, `*`(`^`(t, 4)))), 3))), `*`(`+`(`*`(31, `*`(`^`(t...
(2.8)
 

`
` (2.8)
 

This is a rational elliptic surface; Oguiso-Shioda type No.22. (2.8)
 

`
` (2.8)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (2.8)
 

`
` (2.8)
 

The rank of the Mordell-Weil group over C is 3. (2.8)
 

` ` (2.8)
 

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

2\,{x}^{4}+{y}^{4}-3\,{x}^{2}yz-2\,{y}^{3}z+{y}^{2}{z}^{2}
 

TypeNo.23 

> qc[23]:=(3*x^2+y^2)^2-6*x^2*z^2+2*y^2*z^2;
 

`:=`(qc[23], `+`(`*`(`^`(`+`(`*`(3, `*`(`^`(x, 2))), `*`(`^`(y, 2))), 2)), `-`(`*`(6, `*`(`^`(x, 2), `*`(`^`(z, 2))))), `*`(2, `*`(`^`(y, 2), `*`(`^`(z, 2)))))) (3.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[23]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[23]),x,y);
 

{[[RootOf(`+`(`*`(3, `*`(`^`(_Z, 2))), 1)), 1, 0], 2, 1, 2], [[0, 0, 1], 2, 1, 2]} (3.2)
 

> subs(z=t*(x-y)+2*y,qc[23]);
 

`+`(`*`(`^`(`+`(`*`(3, `*`(`^`(x, 2))), `*`(`^`(y, 2))), 2)), `-`(`*`(6, `*`(`^`(x, 2), `*`(`^`(`+`(`*`(t, `*`(`+`(x, `-`(y)))), `*`(2, `*`(y))), 2))))), `*`(2, `*`(`^`(y, 2), `*`(`^`(`+`(`*`(t, `*`(`... (3.3)
 

> Q23:=mapfactor(subs({y=1,x=U},%),U);
 

`:=`(Q23, `+`(`-`(`*`(4, `*`(t, `*`(`+`(t, `-`(2)), `*`(U))))), `-`(`*`(3, `*`(`+`(`*`(2, `*`(`^`(t, 2))), `-`(3)), `*`(`^`(U, 4))))), `*`(12, `*`(t, `*`(`+`(t, `-`(2)), `*`(`^`(U, 3))))), `-`(`*`(2, ...
`:=`(Q23, `+`(`-`(`*`(4, `*`(t, `*`(`+`(t, `-`(2)), `*`(U))))), `-`(`*`(3, `*`(`+`(`*`(2, `*`(`^`(t, 2))), `-`(3)), `*`(`^`(U, 4))))), `*`(12, `*`(t, `*`(`+`(t, `-`(2)), `*`(`^`(U, 3))))), `-`(`*`(2, ...
(3.4)
 

> subs(U=1,Q23);
simplify(%);
 

`+`(`*`(8, `*`(t, `*`(`+`(t, `-`(2))))), `-`(`*`(8, `*`(`^`(t, 2)))), `*`(16, `*`(t))) (3.5)
 

0 (3.5)
 

> Quartic_to_Weierstrass(Q23,[1,0]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(4, `*`(`^`(t, 2)))), `-`(`*`(48, `*`(t))), 36), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(192, `*`(t, `*`(`+`(t, 3), `*`(`+`(t, `-`(1)), `*...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(4, `*`(`^`(t, 2)))), `-`(`*`(48, `*`(t))), 36), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(192, `*`(t, `*`(`+`(t, 3), `*`(`+`(t, `-`(1)), `*...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`-`(`*`(4, `*`(`^`(t, 2)))), `-`(`*`(48, `*`(t))), 36), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(192, `*`(t, `*`(`+`(t, 3), `*`(`+`(t, `-`(1)), `*...
(3.6)
 

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

`+`(`-`(`*`(12, `*`(t, `*`(`+`(t, 3), `*`(`+`(t, `-`(1)), `*`(`^`(Z, 2), `*`(X))))))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `*`(`+`(`*`(`^`(t, 2)), `*`(12, `*`(t)), `-`(9)), `*`(`^`(X, 2), `*`... (3.7)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (3.8)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(`^`(t, 2))), `-`(`*`(12, `*`(t))), 9), `*`(`^`(x, 2))), `*`(12, `*`(`+`(t, 3), `*`(`+`(t, `-`(1)), `*`(t, `*`(x))))), `-`(`*`(12, `*`(`+`(`*`(2, `*... (3.8)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(`^`(t, 2))), `-`(`*`(12, `*`(t))), 9), `*`(`^`(x, 2))), `*`(12, `*`(`+`(t, 3), `*`(`+`(t, `-`(1)), `*`(t, `*`(x))))), `-`(`*`(12, `*`(`+`(`*`(2, `*... (3.9)
 

Discriminant = `+`(`*`(768, `*`(`^`(t, 3), `*`(`+`(`*`(`^`(t, 3)), `-`(`*`(18, `*`(`^`(t, 2)))), `*`(54, `*`(t)), `-`(54)), `*`(`^`(`+`(`*`(`^`(t, 2)), `-`(`*`(3, `*`(t))), 3), 2)))))) (3.9)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(t, `-`(3)), 12))), `*`(3, `*`(`^`(t, 3), `*`(`+`(`*`(`^`(t, 3)), `-`(`*`(18, `*`(`^`(t, 2)))), `*`(54, `*`(t)), `-`(54)), `*`(`^`(`+`(`*`(`^`(t, ... (3.9)
 

`
` (3.9)
 

This is a rational elliptic surface; Oguiso-Shioda type No.23. (3.9)
 

`
` (3.9)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (3.9)
 

`
` (3.9)
 

The rank of the Mordell-Weil group over C is 3. (3.9)
 

` ` (3.9)
 

TypeNo.24 

> QC[3]:=x^4+y^4+x^2*z^2-y^2*z^2;
 

`:=`(QC[3], `+`(`*`(`^`(x, 4)), `*`(`^`(y, 4)), `*`(`^`(x, 2), `*`(`^`(z, 2))), `-`(`*`(`^`(y, 2), `*`(`^`(z, 2)))))) (4.1)
 

> mapfactor(subs({x=1,y=U},subs(z=t*y,QC[3])),U);
 

`+`(`*`(`^`(t, 2), `*`(`^`(U, 2))), `-`(`*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(U, 4))))), 1) (4.2)
 

> Quartic_to_Weierstrass(%,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`^`(t, 2), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(4, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(X, `*`(`^`(Z, 2))))))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`^`(t, 2), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(4, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(X, `*`(`^`(Z, 2))))))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+...
`+`(`*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`^`(X, 3))), `-`(`*`(`^`(t, 2), `*`(`^`(X, 2), `*`(Z)))), `-`(`*`(4, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(X, `*`(`^`(Z, 2))))))), `-`(`*`(4, `*`(`^`(t, 2), `*`(`+...
(4.3)
 

> Elliptic_surface(%):
Show_data();
 

`
     The curve you have entered is:` (4.4)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`^`(t, 2), `*`(`^`(x, 2))), `*`(4, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(x)))), `*`(4, `*`(`^`(t, 2), `*`(`+`(t, `-`(1)), `*`(`+`(t, 1)))))) (4.4)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`^`(t, 2), `*`(`^`(x, 2))), `*`(4, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(x)))), `*`(4, `*`(`^`(t, 2), `*`(`+`(t, `-`(1)), `*`(`+`(t, 1)))))) (4.4)
 

Discriminant = `+`(`-`(`*`(256, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(`+`(`*`(`^`(t, 4)), `*`(4, `*`(`^`(t, 2))), `-`(4)), 2))))))) (4.4)
 

`+`(jay, `-`(invariant)) = `+`(`-`(`/`(`*`(16, `*`(`^`(`+`(`*`(`^`(t, 4)), 12, `-`(`*`(12, `*`(`^`(t, 2))))), 3))), `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(`+`(`*`(`^`(t, 4)), `*`(4, `*`(`^`(t, 2))... (4.4)
 

`
` (4.4)
 

This is a rational elliptic surface; Oguiso-Shioda type No.24. (4.4)
 

`
` (4.4)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (4.4)
 

`
` (4.4)
 

The rank of the Mordell-Weil group over C is 3. (4.4)
 

` ` (4.4)
 

>
 

 

TypeNo.25 

> qc[25]:=x^4+x^3*z-y^2*z^2;
 

`:=`(qc[25], `+`(`*`(`^`(x, 4)), `*`(`^`(x, 3), `*`(z)), `-`(`*`(`^`(y, 2), `*`(`^`(z, 2)))))) (5.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[25]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[25]),x,y);
 

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

> subs(y=t*x+z,qc[25]);
 

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

> Q25:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q25, `+`(`*`(`^`(U, 4)), `*`(`^`(U, 3)), `-`(`*`(`^`(t, 2), `*`(`^`(U, 2)))), `-`(`*`(2, `*`(t, `*`(U)))), `-`(1))) (5.4)
 

> subs(U=0,Q25);
simplify(%);
 

-1 (5.5)
 

-1 (5.5)
 

> Quartic_to_Weierstrass(Q25,[0,I]);
 

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

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

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

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

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

> Elliptic_surface(%);
 

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

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`^`(t, 2), `*`(`^`(x, 2))), `*`(`+`(`-`(`*`(2, `*`(t))), 4), `*`(x)), 1) (5.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`^`(t, 2), `*`(`^`(x, 2))), `*`(`+`(`-`(`*`(2, `*`(t))), 4), `*`(x)), 1) (5.10)
 

Discriminant = `+`(`-`(`*`(256, `*`(`^`(t, 5)))), `*`(256, `*`(`^`(t, 4))), `-`(`*`(64, `*`(`^`(t, 3)))), `-`(`*`(1920, `*`(`^`(t, 2)))), `*`(6144, `*`(t)), `-`(4528)) (5.10)
 

`+`(jay, `-`(invariant)) = `+`(`-`(`/`(`*`(256, `*`(`^`(`+`(`*`(`^`(t, 4)), `*`(6, `*`(t)), `-`(12)), 3))), `*`(`+`(`*`(16, `*`(`^`(t, 5))), `-`(`*`(16, `*`(`^`(t, 4)))), `*`(4, `*`(`^`(t, 3))), `*`(1... (5.10)
 

`
` (5.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.25. (5.10)
 

`
` (5.10)
 

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

`
` (5.10)
 

The rank of the Mordell-Weil group over C is 2. (5.10)
 

` ` (5.10)
 

TypeNo.26 

> qc[26]:=x^4+y^4-x*y^2*z;
 

`:=`(qc[26], `+`(`*`(`^`(x, 4)), `*`(`^`(y, 4)), `-`(`*`(x, `*`(`^`(y, 2), `*`(z)))))) (6.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[26]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[26]),x,y);
 

{[[0, 0, 1], 3, 3, 2]} (6.2)
 

> subs(y=t*x+z,qc[26]);
 

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

> Q26:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q26, `+`(`*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(U)), `*`(`+`(1, `*`(`^`(t, 4))), `*`(`^`(U, 4))), `*`(`^`(t, 2), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(`^`(U, 3)))), `*`(2, `*`(t, `*`(`+`(`-`(1), `*`... (6.4)
 

> subs(U=0,Q26);
simplify(%);
 

1 (6.5)
 

1 (6.5)
 

> Quartic_to_Weierstrass(Q26,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(X, `*`(Y, `*`(Z)))), `*`(2, `*`(`^`(t, 2), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(Y, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(X, `*`(Y, `*`(Z)))), `*`(2, `*`(`^`(t, 2), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(Y, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(X, `*`(Y, `*`(Z)))), `*`(2, `*`(`^`(t, 2), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(Y, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(X, `*`(Y, `*`(Z)))), `*`(2, `*`(`^`(t, 2), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(Y, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(X, `*`(Y, `*`(Z)))), `*`(2, `*`(`^`(t, 2), `*`(`+`(`*`(4, `*`(t)), `-`(1)), `*`(Y, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`...
(6.6)
 

`+`(`*`(`^`(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), `...
(6.7)
 

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

`+`(`-`(`*`(64, `*`(`+`(1, `-`(`*`(8, `*`(`^`(t, 2)))), `-`(`*`(8, `*`(`^`(t, 5)))), `*`(2, `*`(`^`(t, 4))), `*`(8, `*`(`^`(t, 6)))), `*`(`^`(Z, 3))))), `-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-...
`+`(`-`(`*`(64, `*`(`+`(1, `-`(`*`(8, `*`(`^`(t, 2)))), `-`(`*`(8, `*`(`^`(t, 5)))), `*`(2, `*`(`^`(t, 4))), `*`(8, `*`(`^`(t, 6)))), `*`(`^`(Z, 3))))), `-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-...
`+`(`-`(`*`(64, `*`(`+`(1, `-`(`*`(8, `*`(`^`(t, 2)))), `-`(`*`(8, `*`(`^`(t, 5)))), `*`(2, `*`(`^`(t, 4))), `*`(8, `*`(`^`(t, 6)))), `*`(`^`(Z, 3))))), `-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-...
(6.8)
 

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

`+`(`-`(`*`(`+`(1, `-`(`*`(8, `*`(`^`(t, 2)))), `-`(`*`(8, `*`(`^`(t, 5)))), `*`(2, `*`(`^`(t, 4))), `*`(8, `*`(`^`(t, 6)))), `*`(`^`(Z, 3)))), `-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(2, ...
`+`(`-`(`*`(`+`(1, `-`(`*`(8, `*`(`^`(t, 2)))), `-`(`*`(8, `*`(`^`(t, 5)))), `*`(2, `*`(`^`(t, 4))), `*`(8, `*`(`^`(t, 6)))), `*`(`^`(Z, 3)))), `-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(2, ...
(6.9)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (6.10)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(2, `*`(t, `*`(`+`(`-`(1), `*`(3, `*`(t))), `*`(`^`(x, 2))))), `*`(`+`(`-`(`*`(8, `*`(`^`(t, 3)))), `*`(`^`(t, 2)), `-`(4), `*`(12, `*`(`^`(t, 4)))), `*`(x)), 1... (6.10)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(2, `*`(t, `*`(`+`(`-`(1), `*`(3, `*`(t))), `*`(`^`(x, 2))))), `*`(`+`(`-`(`*`(8, `*`(`^`(t, 3)))), `*`(`^`(t, 2)), `-`(4), `*`(12, `*`(`^`(t, 4)))), `*`(x)), 1... (6.11)
 

Discriminant = `+`(`*`(256, `*`(`^`(t, 4))), `-`(`*`(2048, `*`(`^`(t, 2)))), 3664, `-`(`*`(64, `*`(`^`(t, 3)))), `*`(2304, `*`(t))) (6.11)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(256, `*`(`^`(`+`(`*`(`^`(t, 2)), 12), 3))), `*`(`+`(`*`(16, `*`(`^`(t, 4))), `-`(`*`(128, `*`(`^`(t, 2)))), 229, `-`(`*`(4, `*`(`^`(t, 3)))), `*`(144, `*`(t)))))... (6.11)
 

`
` (6.11)
 

This is a rational elliptic surface; Oguiso-Shioda type No.26. (6.11)
 

`
` (6.11)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (6.11)
 

`
` (6.11)
 

The rank of the Mordell-Weil group over C is 2. (6.11)
 

` ` (6.11)
 

TypeNo.27 

> qc[27]:=x^4+y^4+x^3*y-x*y^2*z;
 

`:=`(qc[27], `+`(`*`(`^`(x, 4)), `*`(`^`(y, 4)), `*`(`^`(x, 3), `*`(y)), `-`(`*`(x, `*`(`^`(y, 2), `*`(z)))))) (7.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[27]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[27]),x,y);
 

{[[0, 0, 1], 3, 3, 2]} (7.2)
 

> subs(z=t*y+2*x,qc[27]);
 

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

> Q27:=mapfactor(subs({x=1,y=U},%),U);
 

`:=`(Q27, `+`(1, `*`(`^`(U, 4)), U, `-`(`*`(`^`(U, 3), `*`(t))), `-`(`*`(2, `*`(`^`(U, 2)))))) (7.4)
 

> subs(U=0,Q27);
simplify(%);
 

1 (7.5)
 

1 (7.5)
 

> Quartic_to_Weierstrass(Q27,[0,1]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(X, `*`(Y, `*`(Z))), `-`(`*`(2, `*`(t, `*`(Y, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `/`(`*`(9, `*`(`^`(X, 2), `*`(Z))), `*`(4)), `*`(4, `*`(X, `*`(`^`(Z, 2)))), `-`(`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(X, `*`(Y, `*`(Z))), `-`(`*`(2, `*`(t, `*`(Y, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `/`(`*`(9, `*`(`^`(X, 2), `*`(Z))), `*`(4)), `*`(4, `*`(X, `*`(`^`(Z, 2)))), `-`(`...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(X, `*`(Y, `*`(Z))), `-`(`*`(2, `*`(t, `*`(Y, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `/`(`*`(9, `*`(`^`(X, 2), `*`(Z))), `*`(4)), `*`(4, `*`(X, `*`(`^`(Z, 2)))), `-`(`...
(7.6)
 

`+`(`*`(`^`(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), `...
(7.7)
 

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

`+`(`-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(64, `*`(`+`(9, `*`(`^`(t, 2))), `*`(`^`(Z, 3))))), `*`(8, `*`(`^`(X, 2), `*`(Z))), `*`(16, `*`(`+`(4, t), `*`(X, `*`(`^`(Z, 2)))))), {y = `+`(Y...
`+`(`-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(64, `*`(`+`(9, `*`(`^`(t, 2))), `*`(`^`(Z, 3))))), `*`(8, `*`(`^`(X, 2), `*`(Z))), `*`(16, `*`(`+`(4, t), `*`(X, `*`(`^`(Z, 2)))))), {y = `+`(Y...
(7.8)
 

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

`+`(`-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`+`(9, `*`(`^`(t, 2))), `*`(`^`(Z, 3)))), `*`(2, `*`(`^`(X, 2), `*`(Z))), `*`(`+`(4, t), `*`(X, `*`(`^`(Z, 2))))) (7.9)
 

> Elliptic_surface(%);
 

`
     The curve you have entered is:` (7.10)
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(2, `*`(`^`(x, 2)))), `*`(`+`(`-`(4), `-`(t)), `*`(x)), 9, `*`(`^`(t, 2))) (7.10)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `-`(`*`(2, `*`(`^`(x, 2)))), `*`(`+`(`-`(4), `-`(t)), `*`(x)), 9, `*`(`^`(t, 2))) (7.11)
 

Discriminant = `+`(`-`(4528), `*`(8768, `*`(t)), `-`(`*`(4128, `*`(`^`(t, 2)))), `*`(640, `*`(`^`(t, 3))), `-`(`*`(432, `*`(`^`(t, 4))))) (7.11)
 

`+`(jay, `-`(invariant)) = `+`(`-`(`/`(`*`(256, `*`(`^`(`+`(16, `*`(3, `*`(t))), 3))), `*`(`+`(283, `-`(`*`(548, `*`(t))), `*`(258, `*`(`^`(t, 2))), `-`(`*`(40, `*`(`^`(t, 3)))), `*`(27, `*`(`^`(t, 4)... (7.11)
 

`
` (7.11)
 

This is a rational elliptic surface; Oguiso-Shioda type No.27. (7.11)
 

`
` (7.11)
 

Typesetting:-mrow(Typesetting:-mrow(Typesetting:-mi( (7.11)
 

`
` (7.11)
 

The rank of the Mordell-Weil group over C is 2. (7.11)
 

(7.11)
 

TypeNo.28 

> qc[28]:=(z^2-x*z-y^2)^2-x^3*y;
 

`:=`(qc[28], `+`(`*`(`^`(`+`(`*`(`^`(z, 2)), `-`(`*`(x, `*`(z))), `-`(`*`(`^`(y, 2)))), 2)), `-`(`*`(`^`(x, 3), `*`(y))))) (8.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[28]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[28]),x,y);
 

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

> subs(y=t*x,qc[28]);
 

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

> Q28:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q28, `+`(`-`(`*`(2, `*`(U))), `-`(`*`(`+`(`*`(2, `*`(`^`(t, 2))), `-`(1)), `*`(`^`(U, 2)))), `*`(t, `*`(`+`(t, `-`(1)), `*`(`+`(`*`(`^`(t, 2)), t, 1), `*`(`^`(U, 4))))), `*`(2, `*`(`^`(t, 2), `*`... (8.4)
 

> subs(U=0,Q28);
simplify(%);
 

1 (8.5)
 

1 (8.5)
 

> Quartic_to_Weierstrass(Q28,[0,1]);
 

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

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

> Elliptic_surface(%);
 

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

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(2, `*`(`^`(t, 2)))), 1), `*`(`^`(x, 2))), `-`(`*`(4, `*`(t, `*`(`+`(t, `*`(`^`(t, 3)), `-`(1)), `*`(x))))), `*`(4, `*`(`^`(t, 3), `*`(`+`(`-`(2), t... (8.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(2, `*`(`^`(t, 2)))), 1), `*`(`^`(x, 2))), `-`(`*`(4, `*`(t, `*`(`+`(t, `*`(`^`(t, 3)), `-`(1)), `*`(x))))), `*`(4, `*`(`^`(t, 3), `*`(`+`(`-`(2), t... (8.10)
 

Discriminant = `+`(`*`(256, `*`(`^`(t, 2), `*`(`+`(`-`(`*`(16, `*`(t))), `*`(16, `*`(`^`(t, 4))), `*`(8, `*`(`^`(t, 2))), 1))))) (8.10)
 

`+`(jay, `-`(invariant)) = `+`(`/`(`*`(16, `*`(`^`(`+`(1, `*`(8, `*`(`^`(t, 2))), `*`(16, `*`(`^`(t, 4))), `-`(`*`(12, `*`(t)))), 3))), `*`(`^`(t, 2), `*`(`+`(`-`(`*`(16, `*`(t))), `*`(16, `*`(`^`(t, ... (8.10)
 

`
` (8.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.28. (8.10)
 

`
` (8.10)
 

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

`
` (8.10)
 

The rank of the Mordell-Weil group over C is 2. (8.10)
 

` ` (8.10)
 

TypeNo.29 

> qc[29]:=(x^2+y^2-3*x*z)^2-4*x^2*(2*z^2-x*z);
 

`:=`(qc[29], `+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(`^`(y, 2)), `-`(`*`(3, `*`(x, `*`(z))))), 2)), `-`(`*`(4, `*`(`^`(x, 2), `*`(`+`(`*`(2, `*`(`^`(z, 2))), `-`(`*`(x, `*`(z)))))))))) (9.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[29]),x,y);
 

Plot_2d
 

> singularities(subs(z=1,qc[29]),x,y);
 

{[[0, 0, 1], 2, 2, 2], [[1, 0, 1], 2, 1, 2]} (9.2)
 

> subs(y=t*(x-2*z),qc[29]);
 

`+`(`*`(`^`(`+`(`*`(`^`(x, 2)), `*`(`^`(t, 2), `*`(`^`(`+`(x, `-`(`*`(2, `*`(z)))), 2))), `-`(`*`(3, `*`(x, `*`(z))))), 2)), `-`(`*`(4, `*`(`^`(x, 2), `*`(`+`(`*`(2, `*`(`^`(z, 2))), `-`(`*`(x, `*`(z)... (9.3)
 

> Q29:=mapfactor(subs({z=1,x=U},%),U);
 

`:=`(Q29, `+`(`-`(`*`(8, `*`(`^`(t, 2), `*`(`+`(`*`(4, `*`(`^`(t, 2))), 3), `*`(U))))), `*`(`+`(1, `*`(24, `*`(`^`(t, 4))), `*`(32, `*`(`^`(t, 2)))), `*`(`^`(U, 2))), `*`(`^`(`+`(`*`(`^`(t, 2)), 1), 2...
`:=`(Q29, `+`(`-`(`*`(8, `*`(`^`(t, 2), `*`(`+`(`*`(4, `*`(`^`(t, 2))), 3), `*`(U))))), `*`(`+`(1, `*`(24, `*`(`^`(t, 4))), `*`(32, `*`(`^`(t, 2)))), `*`(`^`(U, 2))), `*`(`^`(`+`(`*`(`^`(t, 2)), 1), 2...
(9.4)
 

> subs(U=2,Q29);
simplify(%);
 

`+`(`-`(`*`(16, `*`(`^`(t, 2), `*`(`+`(`*`(4, `*`(`^`(t, 2))), 3))))), `-`(12), `*`(48, `*`(`^`(t, 4))), `*`(16, `*`(`^`(t, 2))), `*`(16, `*`(`^`(`+`(`*`(`^`(t, 2)), 1), 2)))) (9.5)
 

4 (9.5)
 

> Quartic_to_Weierstrass(Q29,[2,2]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(12, `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(192, `*`(64, `*`(`^`(t, 2)))), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(12, `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(192, `*`(64, `*`(`^`(t, 2)))), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(12, `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(192, `*`(64, `*`(`^`(t, 2)))), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(12, `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(192, `*`(64, `*`(`^`(t, 2)))), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(12, `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(192, `*`(64, `*`(`^`(t, 2)))), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(12, `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(192, `*`(64, `*`(`^`(t, 2)))), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `*`(16, `*`(`+`(t, `-`(1)), `*`(`+`(t, 1), `*`(`^`(X, ...
(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});
 

`+`(`-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `*`(4, `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(13)), `*`(`^`(X, 2), `*`(Z)))), `*`(128, `*`(`+`(`*`(`^`(t, 2)), `*`(2, `*`(`^`(t, 4))), `-`(7)), `*`(X, `*`...
`+`(`-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `*`(4, `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(13)), `*`(`^`(X, 2), `*`(Z)))), `*`(128, `*`(`+`(`*`(`^`(t, 2)), `*`(2, `*`(`^`(t, 4))), `-`(7)), `*`(X, `*`...
`+`(`-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `*`(4, `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(13)), `*`(`^`(X, 2), `*`(Z)))), `*`(128, `*`(`+`(`*`(`^`(t, 2)), `*`(2, `*`(`^`(t, 4))), `-`(7)), `*`(X, `*`...
(9.8)
 

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

`+`(`-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(13)), `*`(`^`(X, 2), `*`(Z))), `*`(8, `*`(`+`(`*`(`^`(t, 2)), `*`(2, `*`(`^`(t, 4))), `-`(7)), `*`(X, `*`(`^`(Z, 2)...
`+`(`-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(13)), `*`(`^`(X, 2), `*`(Z))), `*`(8, `*`(`+`(`*`(`^`(t, 2)), `*`(2, `*`(`^`(t, 4))), `-`(7)), `*`(X, `*`(`^`(Z, 2)...
(9.9)
 

> Elliptic_surface(%);
 

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

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(4, `*`(`^`(t, 2)))), 13), `*`(`^`(x, 2))), `*`(`+`(`-`(`*`(8, `*`(`^`(t, 2)))), `-`(`*`(16, `*`(`^`(t, 4)))), 56), `*`(x)), 80, `*`(32, `*`(`^`(t, ... (9.10)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(4, `*`(`^`(t, 2)))), 13), `*`(`^`(x, 2))), `*`(`+`(`-`(`*`(8, `*`(`^`(t, 2)))), `-`(`*`(16, `*`(`^`(t, 4)))), 56), `*`(x)), 80, `*`(32, `*`(`^`(t, ... (9.11)
 

Discriminant = `+`(`-`(`*`(131072, `*`(`^`(t, 6), `*`(`+`(`*`(64, `*`(`^`(t, 4))), `-`(1), `*`(88, `*`(`^`(t, 2))))))))) (9.11)
 

`+`(jay, `-`(invariant)) = `+`(`-`(`/`(`*`(`^`(`+`(`*`(8, `*`(`^`(t, 2))), `-`(`*`(8, `*`(t))), `-`(1)), 3), `*`(`^`(`+`(`*`(8, `*`(`^`(t, 2))), `*`(8, `*`(t)), `-`(1)), 3))), `*`(32, `*`(`^`(t, 6), `... (9.11)
 

`
` (9.11)
 

This is a rational elliptic surface; Oguiso-Shioda type No.32. (9.11)
 

`
` (9.11)
 

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

`
` (9.11)
 

The rank of the Mordell-Weil group over C is 2. (9.11)
 

` ` (9.11)
 

TypeNo.30 

> qc[30]:=x^4+y^4-x*y^2*z;
 

`:=`(qc[30], `+`(`*`(`^`(x, 4)), `*`(`^`(y, 4)), `-`(`*`(x, `*`(`^`(y, 2), `*`(z)))))) (10.1)
 

> with(plots):

with(algcurves):
plot_real_curve(subs(z=1,qc[30]),x,y);
 

Plot_2d
 

> singularities(subs(x=1,qc[30]),y,z);
 

{[[0, 1, 0], 3, 3, 2]} (10.2)
 

> subs(z=t*(y-2*x)+2*x,qc[30]);
 

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

> Q30:=mapfactor(subs({x=1,y=U},%),U);
 

`:=`(Q30, `+`(`*`(2, `*`(`+`(t, `-`(1)), `*`(`^`(U, 2)))), `*`(`^`(U, 4)), `-`(`*`(`^`(U, 3), `*`(t))), 1)) (10.4)
 

> subs(U=2,Q30);
simplify(%);
 

9 (10.5)
 

9 (10.5)
 

> Quartic_to_Weierstrass(Q30,[2,3]);
 

`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(24, `-`(`*`(4, `*`(t)))), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(162, `*`(t))), 1296), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(12, `*`(t)), ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(24, `-`(`*`(4, `*`(t)))), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(162, `*`(t))), 1296), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(12, `*`(t)), ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(24, `-`(`*`(4, `*`(t)))), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(162, `*`(t))), 1296), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(12, `*`(t)), ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(24, `-`(`*`(4, `*`(t)))), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(162, `*`(t))), 1296), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(12, `*`(t)), ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(24, `-`(`*`(4, `*`(t)))), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(162, `*`(t))), 1296), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(12, `*`(t)), ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(24, `-`(`*`(4, `*`(t)))), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(162, `*`(t))), 1296), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(12, `*`(t)), ...
`+`(`*`(`^`(Y, 2), `*`(Z)), `*`(`+`(24, `-`(`*`(4, `*`(t)))), `*`(X, `*`(Y, `*`(Z)))), `*`(`+`(`-`(`*`(162, `*`(t))), 1296), `*`(Y, `*`(`^`(Z, 2)))), `-`(`*`(`^`(X, 3))), `-`(`*`(`+`(`*`(12, `*`(t)), ...
(10.6)
 

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

`+`(`-`(`*`(324, `*`(`+`(`*`(`^`(t, 2)), `-`(`*`(14, `*`(t))), 39), `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(729, `*`(`+`(`*`(25, `*`(`^`(t, 2))), `-`(`*`(192, `...
`+`(`-`(`*`(324, `*`(`+`(`*`(`^`(t, 2)), `-`(`*`(14, `*`(t))), 39), `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(729, `*`(`+`(`*`(25, `*`(`^`(t, 2))), `-`(`*`(192, `...
`+`(`-`(`*`(324, `*`(`+`(`*`(`^`(t, 2)), `-`(`*`(14, `*`(t))), 39), `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(729, `*`(`+`(`*`(25, `*`(`^`(t, 2))), `-`(`*`(192, `...
(10.7)
 

> mapfactor(subs({X=9*X,Y=27*Y},%[1])/729,[X,Y]);
 

>
 

`+`(`-`(`*`(4, `*`(`+`(`*`(`^`(t, 2)), `-`(`*`(14, `*`(t))), 39), `*`(X, `*`(`^`(Z, 2)))))), `-`(`*`(`^`(X, 3))), `*`(`^`(Y, 2), `*`(Z)), `-`(`*`(`+`(`*`(25, `*`(`^`(t, 2))), `-`(`*`(192, `*`(t))), 36... (10.8)
 

> Elliptic_surface(%);
 

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

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(4, `*`(t))), 22), `*`(`^`(x, 2))), `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(`*`(56, `*`(t))), 156), `*`(x)), `*`(25, `*`(`^`(t, 2))), `-`(`*`(192, `*`(t... (10.9)
 

> Show_data();
 

`*`(`^`(y, 2)) = `+`(`*`(`^`(x, 3)), `*`(`+`(`-`(`*`(4, `*`(t))), 22), `*`(`^`(x, 2))), `*`(`+`(`*`(4, `*`(`^`(t, 2))), `-`(`*`(56, `*`(t))), 156), `*`(x)), `*`(25, `*`(`^`(t, 2))), `-`(`*`(192, `*`(t... (10.10)
 

Discriminant = `+`(`-`(`*`(16, `*`(`^`(t, 2), `*`(`+`(`-`(768), `*`(832, `*`(t)), `-`(`*`(325, `*`(`^`(t, 2)))), `*`(32, `*`(`^`(t, 3))))))))) (10.10)
 

`+`(jay, `-`(invariant)) = `+`(`-`(`/`(`*`(16384, `*`(`^`(`+`(4, `-`(`*`(2, `*`(t))), `*`(`^`(t, 2))), 3))), `*`(`^`(t, 2), `*`(`+`(`-`(768), `*`(832, `*`(t)), `-`(`*`(325, `*`(`^`(t, 2)))), `*`(32, `... (10.10)
 

`
` (10.10)
 

This is a rational elliptic surface; Oguiso-Shioda type No.30. (10.10)
 

`
` (10.10)
 

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

`
` (10.10)
 

The rank of the Mordell-Weil group over C is 2. (10.10)
 

` ` (10.10)
 

> latex(y^2 = x^3+(-4*t+22)*x^2+(4*t^2-56*t+156)*x+25*t^2-192*t+360);
 

{y}^{2}={x}^{3}+ \left( -4\,t+22 \right) {x}^{2}+ \left( 4\,{t}^{2}-56
 

\,t+156 \right) x+25\,{t}^{2}-192\,t+360
 

>