fact: Definition nat_of_pos_expand (p : positive) : nat := nat_of_pos_rec_expand p 1.
imports: elpi(elpi) Coq(QArith) Coq.micromega(OrderedRing RingMicromega) mathcomp(all_ssreflect ssralg ssrnum ssrint) mathcomp.zify(ssrZ zify)