I think this is a bug. In one Sage session: sage: F4 = GF(4) sage: F16 = GF(16) sage: F4.gen() in F16 True sage: F16.has_coerce_map_from(F4) True

-- all is well. But in a new session: sage: F4 = GF(4, names='a') sage: F16 = GF(16, names='b') sage: F4.gen() in F16 False sage: F16.has_coerce_map_from(F4) False Why should the fact that I have given non-default names to the generators (the default names are z2 and z4) stop the coercion being dicovered? Worse than that, I tried to create my own coercion from F4 to F16 in the second situation and it prevented me from doing so, saying there already was one, while at the same time telling me there was no coercion. Inconsistent! John -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.