Theorem: Matroid.erk_loopyOn_eq_zero (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 : Set α✝
α : Type u_3
⊢ (emptyOn α).erk = 0
Tactic:
rw [erk_eq_zero_iff, emptyOn_ground, loopyOn_empty]
State after:
no goals