fact: Definition prod_tuple (t1 t2 : seq cube) := map (fun n : 'I_6 => nth F0 t2 n) t1.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq div) mathcomp(choice fintype tuple finfun bigop finset fingroup) mathcomp(action perm primitive_action)