fact: Definition m3lmul (l1 l2 : seq Z) := (Z.add (nth Z0 l1 0 * nth Z0 l2 0) (nth Z0 l1 2 * nth Z0 l2 2)) :: (Z.add (nth Z0 l1 2 * nth Z0 l2 2) (nth Z0 l1 1 * nth Z0 l2 1)) :: (Z.add (nth Z0 l1 0 * nth Z0 l2 2) (nth Z0 l1 2 * nth Z0 l2 1)) :: nil.
imports: Coq(Extraction ZArith Lia) mathcomp(all_ssreflect all_algebra)