GROEBPREREDUCE _ _ _ _ _ _ _ _ _ _ _ _ switch

If groebprereduce set ON, groebner and groebnerf try to simplify the input expressions: if the head term of an input expression is a multiple of the head term of another expression, it can be reduced; these reductions are done cyclicly as long as possible in order to shorten the main part of the algorithm.

By default groebprereduce is off.