intro h'
case a.mp
t : ℕ
P : ℕ → ℕ
h : Balanced t P
this : ∀ (i : ℕ), i ∈ range (t + 1) → P i = minP t P ∨ P i = minP t P + 1
a : ℕ
⊢ a ∈ range (t + 1) ∧ P a = minP t P + 1 → a ∈ range (t + 1) ∧ ¬P a = minP t P
case a.mp
t : ℕ
P : ℕ → ℕ
h : Balanced t P
this : ∀ (i : ℕ), i ∈ range (t + 1) → P i = minP t P ∨ P i = minP t P + 1
a : ℕ
h' : a ∈ range (t + 1) ∧ P a = minP t P + 1
⊢ a ∈ range (t + 1) ∧ ¬P a = minP t P