Hint Rewrite <- Zle_is_le_bool: align.
Hint Rewrite Z.eqb_eq: align.
Hint Rewrite power_nat_divide_le using (auto with align): align.
Hint Rewrite Z.mod_divide using (apply two_power_nat_0; auto with align): align.
Hint Rewrite two_p_max_divide using (auto with align): align.
Hint Rewrite two_p_max_1 using (auto with align): align.
Hint Resolve Z_max_two_p: align.

Lemma nth_error_nth:
forall A (al: list A) (z: A) i, (i < length al)%nat -> nth_error al i = Some (nth i al z).