proposition: Lemma fdistAX2 : (fdistX (fdistA P))`2 = (P`1)`1.
proof: Proof. by rewrite /fdistA /fdist_snd /fdistX /fdist_fst /= 3!fdistmap_comp. Qed.
imports: mathcomp(all_ssreflect ssralg fingroup perm matrix) mathcomp(all_algebra vector reals normedtype) mathcomp(mathcomp_extra boolp) mathcomp(Rstruct) ssrR logb realType_ext ssr_ext ssralg_ext bigop_ext