fact: Variables (m n p q : nat) (f : 'I_p -> 'I_q -> 'I_m) (g : 'I_p -> 'I_q -> 'I_n).
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype finfun bigop finset fingroup perm order) mathcomp(div prime binomial ssralg countalg finalg zmodp)