Expansion of ( Sum_{k>=0} k*q^(k^2) )^2.

Terms

a(0) =0a(1) =0a(2) =1a(3) =0a(4) =0a(5) =4a(6) =0a(7) =0a(8) =4a(9) =0a(10) =6a(11) =0a(12) =0a(13) =12a(14) =0a(15) =0a(16) =0a(17) =8a(18) =9a(19) =0a(20) =16a(21) =0a(22) =0a(23) =0a(24) =0a(25) =24a(26) =10a(27) =0a(28) =0a(29) =20