Expansion of 1/(1 - (x + x^2)c(3x)), c(x) the g.f. of A000108.
A110521
Expansion of 1/(1 - (x + x^2)c(3x)), c(x) the g.f. of A000108.
Terms
- a(0) =1a(1) =1a(2) =5a(3) =30a(4) =224a(5) =1871a(6) =16771a(7) =157668a(8) =1533970a(9) =15314626a(10) =156008660a(11) =1615147014a(12) =16944659846a(13) =179746651907
External references
- oeis: A110521