G.f. satisfies: A(x) = exp( Sum_{n>=1} A(x)^n * (x^n/n) / (1 + x^n) ).

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =7a(5) =18a(6) =51a(7) =147a(8) =431a(9) =1295a(10) =3954a(11) =12219a(12) =38174a(13) =120373a(14) =382559a(15) =1224173a(16) =3940964a(17) =12754732a(18) =41476011a(19) =135446194a(20) =444016332a(21) =1460619970a(22) =4819995330a(23) =15951789030a(24) =52932499724a(25) =176073789065a(26) =587010353666