Expansion of (-1 + Product_{k>=1} 1 / (1 + (-x)^k))^4.

Terms

a(0) =1a(1) =0a(2) =4a(3) =4a(4) =10a(5) =16a(6) =26a(7) =44a(8) =63a(9) =100a(10) =144a(11) =212a(12) =297a(13) =420a(14) =584a(15) =796a(16) =1081a(17) =1452a(18) =1940a(19) =2556a(20) =3355a(21) =4372a(22) =5668a(23) =7288a(24) =9327a(25) =11892a(26) =15076a(27) =19012a(28) =23884a(29) =29904