fact: Fixpoint extend_tr (n : nat) {struct n}: (word w (S (n + m))) := match n return (word w (S (n + m))) with | O => v | S n1 => WW W0 (extend_tr n1) end.
imports: ZArith Lia Ndigits BigNumPrelude DoubleType DoubleBase CyclicAxioms DoubleCyclic