a(n) = Sum_{k=0..n} (-1)^k * binomial(n,k^2).

Terms

a(0) =1a(1) =0a(2) =-1a(3) =-2a(4) =-2a(5) =1a(6) =10a(7) =29a(8) =63a(9) =117a(10) =191a(11) =265a(12) =264a(13) =-12a(14) =-1014a(15) =-3654a(16) =-9634a(17) =-21929a(18) =-45424a(19) =-87551a(20) =-158289a(21) =-267616a(22) =-415513a(23) =-563200a(24) =-561430a(25) =12625a(26) =2202084a(27) =8368243a(28) =23532027a(29) =57848882