"Source: Text/Geometry/AlgSrf.text";
"Line: 1525";
"Date: Thu Sep 25 14:47:45 2025";
"Main: Fri Sep 26 14:29:19 2025";
// original file: Text/Geometry/AlgSrf.text, line: 1525
// Example: H126E9 ()
print "Example: H126E9";
ei := GetEchoInput();
SetEchoInput(true);
P3<x,y,z,t> := ProjectiveSpace(Rationals(),3);
Y := Surface(P3,x^5+y^5+z^5+t^5 : Nonsingular := true); //the hypersurface
X := Blowup(Y,Y![0,0,-1,1]);
P<x1,x2,x3,x4,x5,x6,x7,x8,x9> := Ambient(X);
X;
KodairaEnriquesType(X: KnownADE);
mp, is_min := CanonicalWeightedModel(X);
is_min;
assert not $1;
X1 := Codomain(mp); //the canonical model
P<a,b,c,d> := Ambient(X1);
X1;
MinimalChernNumber(X,1) - ChernNumber(X,1);
assert $1 eq 1;
SetEchoInput(ei);
