“…(2) Proof. By the remark after Theorem 4.1, V is determined, up to homomorphic images, by the pair (λ 1 , λ 2 ), which must be a solution of (5). By [3,Corollary 3.8 ] and Proposition 3.7, V is spanned on F by the set ā−2 , ā−1 , ā0 , ā1 ,ā 2 ,ā 3 , s0,1 , and s0,3 .…”