G.f. satisfies: A(x) = G(x*A(x)) where G(x) = A(x/G(x)) = Sum_{n>=0} x^(n(n+1)/2)*(1+x)^n.
A172405
G.f. satisfies: A(x) = G(x*A(x)) where G(x) = A(x/G(x)) = Sum_{n>=0} x^(n(n+1)/2)*(1+x)^n.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =5a(4) =15a(5) =47a(6) =153a(7) =515a(8) =1782a(9) =6293a(10) =22576a(11) =82043a(12) =301417a(13) =1117693a(14) =4177687a(15) =15723545a(16) =59538258a(17) =226656336a(18) =866983080a(19) =3330496250a(20) =12843380569a(21) =49700905874a(22) =192942347560a(23) =751191150163
External references
- oeis: A172405