congr! with a b c
α : Type
inst✝¹ : DecidableEq α
σ : Type
inst✝ : DecidableEq σ
e : EpsilonNFA α σ
starting_state_list : List σ
state : σ
⊢ (∃ s ∈ starting_state_list,
      Relation.ReflTransGen (fun a b => ∃ l, (a, l) ∈ epsilon_arrow_list_to_graph e.epsilon_arrow_list ∧ b ∈ l) s
        state) ↔
    ∃ start_state ∈ starting_state_list, e.toAbstract.EpsilonClosure start_state state
case a.h.e'_2.h.h.e'_2.h.e.h.e'_2.h.h.a
α : Type
inst✝¹ : DecidableEq α
σ : Type
inst✝ : DecidableEq σ
e : EpsilonNFA α σ
starting_state_list : List σ
state a b c : σ
⊢ (∃ l, (b, l) ∈ epsilon_arrow_list_to_graph e.epsilon_arrow_list ∧ c ∈ l) ↔ e.toAbstract.epsilon b c