"Source: Text/Geometry/ModAbVar.text";
"Line: 3177";
"Date: Thu Sep 25 14:47:45 2025";
"Main: Fri Sep 26 14:29:19 2025";
// original file: Text/Geometry/ModAbVar.text, line: 3177
// Example: H148E58 ()
print "Example: H148E58";
ei := GetEchoInput();
SetEchoInput(true);
J := JZero(37);
phi := HeckeOperator(J,2);
phi(J);
Image(phi);
G := nTorsionSubgroup(J,2); G;
phi(G);
IsSurjective(phi-1);
assert $1;
psi := phi-1;
H := G@@(psi); H;  
psi(H);
H := G@@psi; H;
psi(H);
SetEchoInput(ei);
