Theorem: Matroid.erk_loopyOn (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
⊢ (loopyOn E).erk = 0
Tactic:
simp [← (show (loopyOn E).Base ∅ by simp).encard]
State after:
no goals

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
⊢ (loopyOn E).Base ∅
Tactic:
simp
State after:
no goals