modstd for modified cyclic5: still running after 140 hours

[seelisch]

reminder for Stefan + Gerhard

modstd for modified cyclic5 (last generator modified by n = product of all primes <= 1.000.000.000)

Magma needs 4 to 5 hours on wawa to compute the result; SINGULAR is still running after 140 hours; SINGULAR output with option(prot) available on Franks PC

Here's the SINGULAR code:

option(prot); timer = 1; "loading n1..."; bigint n = system("GNUmpLoad", "prod0-1_0.txt"); "loaded n1."; "setting up ring..."; ring R = 0, (x1, x2, x3, x4, x5), dp; "set up ring."; "building ideal I0 (original cyclic5)"; ideal I0 = x1+x2+x3+x4+x5, x1*x2+x2*x3+x3*x4+x4*x5+x5*x1, x1*x2*x3+x2*x3*x4+x3*x4*x5+x4*x5*x1+x5*x1*x2, x1*x2*x3*x4+x2*x3*x4*x5+x3*x4*x5*x1+x4*x5*x1*x2+x5*x1*x2*x3, x1*x2*x3*x4*x5 - 1; "ideal I0 built."; "computing a Gröbner basis of I0 (using modstd)..."; LIB "modstd.lib"; system("--ticks-per-sec", 1000); int t = timer; ideal B0 = modStd(I0); t = timer - t; "Gröbner basis computation for I0 done; time =", t; write(":w B0.txt", B0); "building ideal I1 (modified cyclic5 'gen5 += n')"; ideal I1 = x1+x2+x3+x4+x5, x1*x2+x2*x3+x3*x4+x4*x5+x5*x1, x1*x2*x3+x2*x3*x4+x3*x4*x5+x4*x5*x1+x5*x1*x2, x1*x2*x3*x4+x2*x3*x4*x5+x3*x4*x5*x1+x4*x5*x1*x2+x5*x1*x2*x3, x1*x2*x3*x4*x5 - 1 + n; "ideal I1 built."; "computing a Gröbner basis of I1 (using modstd)..."; t = timer; ideal B1 = modStd(I1, 1, 0, 50, 100); t = timer - t; "Gröbner basis computation for I1 done; time =", t; write(":w B1.txt", B1);