exact hfb
case inr
round : ℕ → ℕ
n a b : ℕ
npos : 0 < n
hfaithful₀ : faithful₀ n round
hfaithful₁ : faithful₁ n round
hfa : trunc n a = a
hfb : trunc n b = b
hba : b ≤ a
hba' : a ≤ 2 * b
hf : round (a - b) = a - b
⊢ trunc n b = b
no goals