G.f. = (1 + 4 * g.f. for A096661)/(1 + 2 Sum_{m>=1} (-1)^m*q^(m^2)).

Terms

a(0) =1a(1) =2a(2) =0a(3) =4a(4) =2a(5) =4a(6) =4a(7) =8a(8) =8a(9) =10a(10) =12a(11) =16a(12) =20a(13) =24a(14) =28a(15) =36a(16) =42a(17) =48a(18) =60a(19) =72a(20) =84a(21) =100a(22) =116a(23) =136a(24) =160a(25) =186a(26) =216a(27) =252a(28) =292a(29) =336