fact: Definition Stern_bij x := if (x<=0) then 0%N else nat_of_pos(Stern_bij1 x).
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq choice fintype order bigop ssralg) mathcomp(div ssrnum ssrint rat prime path binomial) mathcomp(tuple finset) gaia(fibm)