simplify and (maybe) fix generators_to_power_p
simplify and (maybe) fix generators_to_power_p

mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs