L.g.f.: Sum_{n=-oo..+oo} (x - x^(2*n-1))^(2*n-1) / (2*n-1).

Terms

a(0) =1a(1) =4a(2) =1a(3) =15a(4) =1a(5) =12a(6) =40a(7) =16a(8) =1a(9) =77a(10) =92a(11) =24a(12) =101a(13) =28a(14) =204a(15) =373a(16) =1a(17) =36a(18) =667a(19) =40a(20) =575a(21) =689a(22) =826a(23) =48a(24) =393a(25) =1582a(26) =1379a(27) =1937a(28) =590a(29) =60