Theorem: Associates.count_mul_of_coprime
File: Mathlib/RingTheory/UniqueFactorizationDomain.lean

Proof steps:
state_before: α : Type u_1
inst✝⁴ : CancelCommMonoidWithZero α
inst✝³ : UniqueFactorizationMonoid α
inst✝² : DecidableEq (Associates α)
inst✝¹ : (p : Associates α) → Decidable (Irreducible p)
inst✝ : DecidableEq (Associates α)
a b : Associates α
hb : b ≠ 0
p : Associates α
hp : Irreducible p
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
⊢ p.count a.factors = 0 ∨ p.count a.factors = p.count (a * b).factors
state_after: case pos
α : Type u_1
inst✝⁴ : CancelCommMonoidWithZero α
inst✝³ : UniqueFactorizationMonoid α
inst✝² : DecidableEq (Associates α)
inst✝¹ : (p : Associates α) → Decidable (Irreducible p)
inst✝ : DecidableEq (Associates α)
a b : Associates α
hb : b ≠ 0
p : Associates α
hp : Irreducible p
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
ha : a = 0
⊢ p.count a.factors = 0 ∨ p.count a.factors = p.count (a * b).factors

case neg
α : Type u_1
inst✝⁴ : CancelCommMonoidWithZero α
inst✝³ : UniqueFactorizationMonoid α
inst✝² : DecidableEq (Associates α)
inst✝¹ : (p : Associates α) → Decidable (Irreducible p)
inst✝ : DecidableEq (Associates α)
a b : Associates α
hb : b ≠ 0
p : Associates α
hp : Irreducible p
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
ha : ¬a = 0
⊢ p.count a.factors = 0 ∨ p.count a.factors = p.count (a * b).factors
tactic: by_cases ha : a = 0
state_before: case neg
α : Type u_1
inst✝⁴ : CancelCommMonoidWithZero α
inst✝³ : UniqueFactorizationMonoid α
inst✝² : DecidableEq (Associates α)
inst✝¹ : (p : Associates α) → Decidable (Irreducible p)
inst✝ : DecidableEq (Associates α)
a b : Associates α
hb : b ≠ 0
p : Associates α
hp : Irreducible p
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
ha : ¬a = 0
⊢ p.count a.factors = 0 ∨ p.count a.factors = p.count (a * b).factors
state_after: case neg.inl
α : Type u_1
inst✝⁴ : CancelCommMonoidWithZero α
inst✝³ : UniqueFactorizationMonoid α
inst✝² : DecidableEq (Associates α)
inst✝¹ : (p : Associates α) → Decidable (Irreducible p)
inst✝ : DecidableEq (Associates α)
a b : Associates α
hb : b ≠ 0
p : Associates α
hp : Irreducible p
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
ha : ¬a = 0
hz : p.count a.factors = 0
⊢ p.count a.factors = 0 ∨ p.count a.factors = p.count (a * b).factors

case neg.inr
α : Type u_1
inst✝⁴ : CancelCommMonoidWithZero α
inst✝³ : UniqueFactorizationMonoid α
inst✝² : DecidableEq (Associates α)
inst✝¹ : (p : Associates α) → Decidable (Irreducible p)
inst✝ : DecidableEq (Associates α)
a b : Associates α
hb : b ≠ 0
p : Associates α
hp : Irreducible p
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
ha : ¬a = 0
hb0 : p.count b.factors = 0
⊢ p.count a.factors = 0 ∨ p.count a.factors = p.count (a * b).factors
tactic: cases' count_of_coprime ha hb hab hp with hz hb0
state_before: case neg.inr
α : Type u_1
inst✝⁴ : CancelCommMonoidWithZero α
inst✝³ : UniqueFactorizationMonoid α
inst✝² : DecidableEq (Associates α)
inst✝¹ : (p : Associates α) → Decidable (Irreducible p)
inst✝ : DecidableEq (Associates α)
a b : Associates α
hb : b ≠ 0
p : Associates α
hp : Irreducible p
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
ha : ¬a = 0
hb0 : p.count b.factors = 0
⊢ p.count a.factors = 0 ∨ p.count a.factors = p.count (a * b).factors
state_after: case neg.inr.h
α : Type u_1
inst✝⁴ : CancelCommMonoidWithZero α
inst✝³ : UniqueFactorizationMonoid α
inst✝² : DecidableEq (Associates α)
inst✝¹ : (p : Associates α) → Decidable (Irreducible p)
inst✝ : DecidableEq (Associates α)
a b : Associates α
hb : b ≠ 0
p : Associates α
hp : Irreducible p
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
ha : ¬a = 0
hb0 : p.count b.factors = 0
⊢ p.count a.factors = p.count (a * b).factors
tactic: apply Or.intro_right
state_before: case neg.inr.h
α : Type u_1
inst✝⁴ : CancelCommMonoidWithZero α
inst✝³ : UniqueFactorizationMonoid α
inst✝² : DecidableEq (Associates α)
inst✝¹ : (p : Associates α) → Decidable (Irreducible p)
inst✝ : DecidableEq (Associates α)
a b : Associates α
hb : b ≠ 0
p : Associates α
hp : Irreducible p
hab : ∀ (d : Associates α), d ∣ a → d ∣ b → ¬Prime d
ha : ¬a = 0
hb0 : p.count b.factors = 0
⊢ p.count a.factors = p.count (a * b).factors
state_after: no goals
tactic: rw [count_mul ha hb hp, hb0, add_zero]