proposition: Lemma testbit_succ_r a (b:bool) n : 0<=n -> testbit (2*a+b) (succ n) = testbit a n.
proof: Proof. destruct b; simpl; rewrite ?add_0_r. - now apply testbit_odd_succ. - now apply testbit_even_succ. Qed.
imports: Bool ZAxioms ZMulOrder ZPow ZDivFloor ZSgnAbs ZParity NZLog