fact: Variable spec_div21 : forall a1 a2 b, wB/2 <= [|b|] -> [|a1|] < [|b|] -> let (q,r) := w_div21 a1 a2 b in [|a1|] *wB+ [|a2|] = [|q|] * [|b|] + [|r|] /\ 0 <= [|r|] < [|b|].
imports: ZArith Ndigits Lia BigNumPrelude DoubleType DoubleBase