Guess the missing item from this list: α-4, β-4, α-3, β-2, α-1, α-8, α-7, β-5, α-0, α-6, β-0, α-9, β-6, β-3, α-5, α-2.
Directly answer with only one item. Item format should match the list format. Provide no explanation. Answer format: "{item}."