sympy/sympy — pull request #1614 by pernici (2012-10-26 11:26:25+00:00)
Title: replaced the schreier_sims method with Jerrum filter with the incremental one

Eliminated Jerrum filter, used schreier_sims_incremental which is faster asymptotically.

Optimized code reducing the calls to PermutationGroup and using the array form of permutations
more often.

Now the tests run more than 3 times faster on my computer.

This PR replaces https://github.com/sympy/sympy/pull/1562