Theorem: Matroid.loopyOn_erk_eq (Matroid/Rank.lean)

State before:
α : Type u_1
ι : Type u_2
M N : Matroid α
I B X X' Y Y' Z R : Set α
n : ℕ∞
e f : α
E✝ E : Set α
⊢ (loopyOn E).erk = 0
Tactic:
rw [erk_eq_er_ground, loopyOn_er_eq]
State after:
no goals