G.f. A(x) satisfies: -x^3 = Sum_{n=-oo..oo} (-1)^n * x^(n*(n+1)/2) * A(x)^(n*(n-1)/2).

Terms

a(0) =1a(1) =0a(2) =0a(3) =1a(4) =3a(5) =9a(6) =22a(7) =54a(8) =135a(9) =368a(10) =1060a(11) =3135a(12) =9295a(13) =27472a(14) =81309a(15) =242255a(16) =728429a(17) =2208483a(18) =6736523a(19) =20634196a(20) =63410076a(21) =195467757a(22) =604457802a(23) =1875053982a(24) =5833449236a(25) =18195767301a(26) =56888745654a(27) =178238369769a(28) =559538565187