G.f.: A(x) = 1+x + Sum_{n>=2} Product_{k=1..n} (A(x)^k - 1).
A224885
G.f.: A(x) = 1+x + Sum_{n>=2} Product_{k=1..n} (A(x)^k - 1).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =15a(4) =143a(5) =1552a(6) =18282a(7) =228174a(8) =2976534a(9) =40256580a(10) =561755676a(11) =8066942027a(12) =119104886610
External references
- oeis: A224885