Theorem: LO.FirstOrder.Rew.substs_mbar_zero_comp_shift_eq_free (Logic/FirstOrder/Basic/Syntax/Rew.lean)

State before:
L : Language
L' : Language
L₁ : Language
L₂ : Language
L₃ : Language
ξ : Type u_1
ξ' : Type u_2
ξ₁ : Type u_3
ξ₂ : Type u_4
ξ₃ : Type u_5
n n₁ n₂ n₃ : ℕ
ω : Rew L ξ₁ n₁ ξ₂ n₂
⊢ (substs ![&0]).comp shift = free
Tactic:
ext x <;> simp[comp_app, Fin.eq_zero]
State after:
no goals