case mp
R : Type u
inst✝³ : Semiring R
inst✝² : Nontrivial R
p q : ℕ
inst✝¹ : CharP R p
inst✝ : ExpChar R q
⊢ q = 1 → p = 0

case mpr
R : Type u
inst✝³ : Semiring R
inst✝² : Nontrivial R
p q : ℕ
inst✝¹ : CharP R p
inst✝ : ExpChar R q
⊢ p = 0 → q = 1
R : Type u
inst✝³ : Semiring R
inst✝² : Nontrivial R
p q : ℕ
inst✝¹ : CharP R p
inst✝ : ExpChar R q
⊢ q = 1 ↔ p = 0
constructor
case mp
R : Type u
inst✝³ : Semiring R
inst✝² : Nontrivial R
p : ℕ
inst✝¹ : CharP R p
inst✝ : ExpChar R 1
⊢ p = 0
case mp
R : Type u
inst✝³ : Semiring R
inst✝² : Nontrivial R
p q : ℕ
inst✝¹ : CharP R p
inst✝ : ExpChar R q
⊢ q = 1 → p = 0
rintro rfl
no goals
case mp
R : Type u
inst✝³ : Semiring R
inst✝² : Nontrivial R
p : ℕ
inst✝¹ : CharP R p
inst✝ : ExpChar R 1
⊢ p = 0
exact char_zero_of_expChar_one R p
case mpr
R : Type u
inst✝³ : Semiring R
inst✝² : Nontrivial R
q : ℕ
inst✝¹ : ExpChar R q
inst✝ : CharP R 0
⊢ q = 1
case mpr
R : Type u
inst✝³ : Semiring R
inst✝² : Nontrivial R
p q : ℕ
inst✝¹ : CharP R p
inst✝ : ExpChar R q
⊢ p = 0 → q = 1
rintro rfl
no goals
case mpr
R : Type u
inst✝³ : Semiring R
inst✝² : Nontrivial R
q : ℕ
inst✝¹ : ExpChar R q
inst✝ : CharP R 0
⊢ q = 1
exact expChar_one_of_char_zero R q