Local Infix "⇡" := nat_join (at level 50, left associativity).Local Notation power := (mscal mult 1).

Theorem Code_mult_diophantine l q a b c : 𝔻P l -> 𝔻P q -> 𝔻P a -> 𝔻P b -> 𝔻P c -> 𝔻R (fun v => Code_mult (l v) (q v) (a v) (b v) (c v)).