apply Nat.not_le_of_gt
x✝ : Variable
p : LoopProgram
h : len p = 0 ∧ x✝.index = 0
⊢ False
case h
x✝ : Variable
p : LoopProgram
h : len p = 0 ∧ x✝.index = 0
⊢ ?n > ?m

case a
x✝ : Variable
p : LoopProgram
h : len p = 0 ∧ x✝.index = 0
⊢ ?n ≤ ?m

case n
x✝ : Variable
p : LoopProgram
h : len p = 0 ∧ x✝.index = 0
⊢ ℕ

case m
x✝ : Variable
p : LoopProgram
h : len p = 0 ∧ x✝.index = 0
⊢ ℕ