Dirichlet g.f.: Product_{k>=2} (1 + k^(-s))^(k^2).

Terms

a(0) =1a(1) =4a(2) =9a(3) =22a(4) =25a(5) =72a(6) =49a(7) =132a(8) =117a(9) =200a(10) =121a(11) =486a(12) =169a(13) =392a(14) =450a(15) =729a(16) =289a(17) =1116a(18) =361a(19) =1350a(20) =882a(21) =968a(22) =529a(23) =3132a(24) =925a(25) =1352a(26) =1542a(27) =2646a(28) =841a(29) =4500