Notation Zeven_bool_succ := Z.even_succ (only parsing).Notation Zeven_bool_pred := Z.even_pred (only parsing).Notation Zodd_bool_succ := Z.odd_succ (only parsing).Notation Zodd_bool_pred := Z.odd_pred (only parsing).

Theorem Zodd_2p_plus_1 p : Zodd (2 * p + 1).