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

Terms

a(0) =1a(1) =-2a(2) =5a(3) =-15a(4) =54a(5) =-226a(6) =1041a(7) =-5045a(8) =25090a(9) =-126674a(10) =646764a(11) =-3335207a(12) =17359589a(13) =-91138625a(14) =482237135a(15) =-2569446532a(16) =13774698084a(17) =-74245779493a(18) =402105384051