proposition: Lemma shiftl_negate_1_fourth x : x ≪ (-2) = x / 4.
proof: Proof. change (id (x ≪ (-2)) = id x / 4). now apply shiftl_negate_1_to_fourth. Qed.
imports: Coq.setoid_ring.Ring MathClasses.interfaces.abstract_algebra MathClasses.interfaces.naturals MathClasses.interfaces.integers MathClasses.interfaces.additional_operations MathClasses.interfaces.orders