rename_i ih
case cons
head✝ : UInt8
tail✝ : List UInt8
tail_ih✝ : ∀ {acc : Array UInt8} {n : Nat}, Array.size (aux acc n tail✝) = Array.size acc + n
acc : Array UInt8
n : Nat
⊢ Array.size (aux acc n (head✝ :: tail✝)) = Array.size acc + n
case cons
head✝ : UInt8
tail✝ : List UInt8
ih : ∀ {acc : Array UInt8} {n : Nat}, Array.size (aux acc n tail✝) = Array.size acc + n
acc : Array UInt8
n : Nat
⊢ Array.size (aux acc n (head✝ :: tail✝)) = Array.size acc + n