Expansion of Product_{k>=1} (1 + x^k)^prime(k+1).

Terms

a(0) =1a(1) =3a(2) =8a(3) =23a(4) =57a(5) =137a(6) =317a(7) =705a(8) =1524a(9) =3224a(10) =6667a(11) =13521a(12) =26980a(13) =52985a(14) =102624a(15) =196248a(16) =370849a(17) =693159a(18) =1282537a(19) =2350584a(20) =4269912a(21) =7692044a(22) =13748080a(23) =24390170a(24) =42966637a(25) =75187515a(26) =130737631a(27) =225957706a(28) =388279308a(29) =663533206