case step.refl.time e' _ e => exact absurd ht.symm $ ne_of_lt $ lt_of_lt_of_le e.tag_lt e'.tag_le
α : Type
inst✝ : Proper α
s s₁ s₂ s₂✝ s₃✝ : State α
e' : Steps s₂✝ s₃✝
a_ih✝ : Steps s₂✝ s₂ → State.Nontrivial s₂✝ → s₃✝.tag = s₂.tag → s₃✝.progress = s₂.progress → s₃✝ = s₂
ht : s₃✝.tag = s₂.tag
hp : s₃✝.progress = s₂.progress
n : State.Nontrivial s₂
e : s₂ ↓ₜ s₂✝
⊢ s₃✝ = s₂
no goals