Expansion of Product_{i>0, j>0, k>0} (1 + x^(i^2 + j^2 + k^2)).

Terms

a(0) =1a(1) =0a(2) =0a(3) =1a(4) =0a(5) =0a(6) =3a(7) =0a(8) =0a(9) =6a(10) =0a(11) =3a(12) =7a(13) =0a(14) =9a(15) =13a(16) =0a(17) =18a(18) =19a(19) =3a(20) =39a(21) =28a(22) =9a(23) =66a(24) =42a(25) =33a(26) =105a(27) =68a(28) =78a(29) =168