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

Terms

a(0) =1a(1) =1a(2) =3a(3) =8a(4) =26a(5) =82a(6) =285a(7) =995a(8) =3613a(9) =13319a(10) =50053a(11) =190459a(12) =733555a(13) =2851945a(14) =11181927a(15) =44155907a(16) =175470374a(17) =701164361a(18) =2815635000a(19) =11356456980a(20) =45986353012a(21) =186882752814a(22) =761942170718