intro x
case e_a.a
t : ℕ
P : ℕ → ℕ
h : Balanced t P
f : ℕ → ℕ
⊢ ∀ (x : ℕ), x ∈ filter (fun i => P i = minP t P + 1) (range (t + 1)) → f (P x) = f (minP t P + 1)
case e_a.a
t : ℕ
P : ℕ → ℕ
h : Balanced t P
f : ℕ → ℕ
x : ℕ
⊢ x ∈ filter (fun i => P i = minP t P + 1) (range (t + 1)) → f (P x) = f (minP t P + 1)