G.f. A(x) satisfies: A(x) = x / [Sum_{n>=1} (-1)^(n-1) * A(x)^(n*(n-1)/2) * (1 - A(x)^n)/(1 - A(x))].
A209335
G.f. A(x) satisfies: A(x) = x / [Sum_{n>=1} (-1)^(n-1) * A(x)^(n*(n-1)/2) * (1 - A(x)^n)/(1 - A(x))].
Terms
- a(0) =1a(1) =1a(2) =3a(3) =9a(4) =31a(5) =111a(6) =415a(7) =1591a(8) =6229a(9) =24773a(10) =99793a(11) =406197a(12) =1667803a(13) =6898183a(14) =28710933a(15) =120146889a(16) =505161063a(17) =2132805899a(18) =9037954725a(19) =38424844083a(20) =163843435737a(21) =700477124863
External references
- oeis: A209335