simpa [exp_inj.eq_iff] using
  lenbit_sub_pow2_iff_of_lenbit (exp_pow2 i) (exp_pow2 j) h
case pos
M : Type u_1
inst✝⁵ : Zero M
inst✝⁴ : One M
inst✝³ : Add M
inst✝² : Mul M
inst✝¹ : LT M
inst✝ : M ⊧ₘ* 𝐈𝚺₁
i j a : M
h : j ∈ a
⊢ i ∈ a - exp j ↔ ¬i = j ∧ i ∈ a
no goals