CoCoA » CoCoA-5

In the example below ImplicitModular decides that it has found a "better prime", but after that all primes seem to be "bad".
Very suspicious!

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source("../IdealsModP.cpkg5");
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SetVerbosityLevel(90);

R ::= QQ[x,y,z,v,w];
Use S ::= QQ[s,t];
f1:= t^5*s^2 -s -1;  f2:= s^3*t^2 +2*t^2 -t;  f3:= t^2 +s*t -1;  f4:=s^3-2*t+s; f5:= s^3-t^2;
L := [f1, f2, f3,f4, f5];
T := CpuTime();  G:= implicit(R,L); TimeFrom(T);
-- 4.643
T := CpuTime();  GM:= ImplicitModular(R,L,100); TimeFrom(T);
-- 6.820

This is just Renzo's example 3su6.cocoa5 (from IdealsModp) with starting prime 100.