fact: Fixpoint add_pos_nat (p : positive) (n : nat) : nat := match p with | p0~1 => S (add_pos_nat p0 (add_pos_nat p0 n)) | p0~0 => add_pos_nat p0 (add_pos_nat p0 n) | 1 => S n end%positive.
imports: elpi(elpi) Coq(QArith) Coq.micromega(OrderedRing RingMicromega) mathcomp(all_ssreflect ssralg ssrnum ssrint) mathcomp.zify(ssrZ zify)