G.f.: Sum_{k>=0} x^(2^k) / (1 - x^(2^k))^4.

Terms

a(0) =1a(1) =5a(2) =10a(3) =25a(4) =35a(5) =66a(6) =84a(7) =145a(8) =165a(9) =255a(10) =286a(11) =430a(12) =455a(13) =644a(14) =680a(15) =961a(16) =969a(17) =1305a(18) =1330a(19) =1795a(20) =1771a(21) =2310a(22) =2300a(23) =3030a(24) =2925a(25) =3731a(26) =3654a(27) =4704a(28) =4495a(29) =5640