p : ℕ → Prop
inst✝ : DecidablePred p
m n : ℕ
hm : p m
hn : p n
heq : count p m = count p n
h : m ≠ n
⊢ False
p : ℕ → Prop
inst✝ : DecidablePred p
m n : ℕ
hm : p m
hn : p n
heq : count p m = count p n
⊢ m = n
by_contra' h : m ≠ n
case inr
p : ℕ → Prop
inst✝ : DecidablePred p
m n : ℕ
hm : p m
hn : p n
heq : count p m = count p n
h : m ≠ n
this : ∀ {p : ℕ → Prop} [inst : DecidablePred p] {m n : ℕ}, p m → p n → count p m = count p n → m ≠ n → m < n → False
hmn : ¬m < n
⊢ False

p✝ : ℕ → Prop
inst✝¹ : DecidablePred p✝
p : ℕ → Prop
inst✝ : DecidablePred p
m n : ℕ
hm : p m
hn : p n
heq : count p m = count p n
h : m ≠ n
hmn : m < n
⊢ False
p : ℕ → Prop
inst✝ : DecidablePred p
m n : ℕ
hm : p m
hn : p n
heq : count p m = count p n
h : m ≠ n
⊢ False
wlog hmn : m < n
no goals
case inr
p : ℕ → Prop
inst✝ : DecidablePred p
m n : ℕ
hm : p m
hn : p n
heq : count p m = count p n
h : m ≠ n
this : ∀ {p : ℕ → Prop} [inst : DecidablePred p] {m n : ℕ}, p m → p n → count p m = count p n → m ≠ n → m < n → False
hmn : ¬m < n
⊢ False
exact this hn hm heq.symm h.symm (h.lt_or_lt.resolve_left hmn)
no goals
p✝ : ℕ → Prop
inst✝¹ : DecidablePred p✝
p : ℕ → Prop
inst✝ : DecidablePred p
m n : ℕ
hm : p m
hn : p n
heq : count p m = count p n
h : m ≠ n
hmn : m < n
⊢ False
simpa [heq] using count_strict_mono hm hmn