On Qua, 2009-04-29 at 18:12 +0100, Leo Butler wrote: > Apparently, this depends on the underlying lisp, as you can see below. > (%o4) (x^2+x+1)*(x^4+x^3+1) For the record, I get that same result with clisp, sbcl and clozure cl. But with gcl I get: (x^2-x+1)*(-x^4+x^3+1) Jaime