exact lem
t : Th
Δ : Ctx
b : Lex (ℕ × ℕ)
i j : ℕ
lem : lindenbaumSequence t Δ (i, j) ≤ lindenbaumSequence t Δ (i, j + 1)
a₁ b₁ : ℕ
h₂ : a₁ < i
l₁ : a₁ < i ∨ a₁ = i ∧ b₁ ≤ j
l₂ : ↑toLex (a₁, b₁) ≤ ↑toLex (i, j)
l₃ : lindenbaumSequence t Δ (a₁, b₁) ⊆ lindenbaumSequence t Δ (i, j)
⊢ lindenbaumSequence t Δ (i, j) ≤ lindenbaumSequence t Δ (i, j + 1)
no goals