α : Type u
β : Type v
γ : Type w
s : Seq α
n : ℕ
⊢ tail (drop (↑s) n) = ↑(Seq.tail (Seq.drop s n))
α : Type u
β : Type v
γ : Type w
s : Seq α
n : ℕ
⊢ drop (↑s) (n + 1) = ↑(Seq.drop s (n + 1))
simp only [drop, Nat.add_eq, add_zero, Seq.drop]
no goals
α : Type u
β : Type v
γ : Type w
s : Seq α
n : ℕ
⊢ tail (drop (↑s) n) = ↑(Seq.tail (Seq.drop s n))
rw [dropn_ofSeq s n, tail_ofSeq]