fact: Definition rfd_fun p := [fun u => Sub ((_ : {perm T}) _) (rfd_funP p u) : T'].
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(div fintype tuple tuple bigop prime finset fingroup) mathcomp(morphism perm automorphism quotient action cyclic) mathcomp(pgroup gseries sylow primitive_action)