13128240840
domain: N
Appears in sequences
- Expansion of (1 + x*C)*C, where C = (1 - (1 - 4*x)^(1/2))/(2*x) is the g.f. for Catalan numbers, A000108.at n=20A068875
- Expansion of exp( arcsinh( -2*x ) ) in powers of x.at n=42A104624
- Expansion of exp( arcsinh( 2*x ) ).at n=42A182122
- The number of boundary twigs for complete binary twigs. A twig is a vertex with one edge on the boundary and only one other descendant.at n=19A228403
- Certain directed lattice paths.at n=10A260775
- Number of rooted asymmetrical polyenoids of type U_n* having n edges.at n=20A262543
- a(-1)=-1; a(n) = 2*A000108(n) for n >= 0.at n=21A284016