Theorem: Matroid.loopyOn_r_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 X : Set α
⊢ (loopyOn E).r X = 0
Tactic:
rw [← er_toNat_eq_r, loopyOn_er_eq]
State after:
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 X : Set α
⊢ toNat 0 = 0

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 X : Set α
⊢ toNat 0 = 0
Tactic:
rfl
State after:
no goals