exact ⟨{hE.some}, ⟨_, hE.some_mem, rfl⟩, by simp⟩
α : Type u_1
M : Matroid α
C C' I X K C₁ C₂ R : Set α
e f x y : α
E D : Set α
hE : E.Nonempty
x✝ : (loopyOn E)✶.RkPos
⊢ ∃ C, (∃ e ∈ E, C = {e}) ∧ C.encard ≤ 1
no goals