259289580
domain: N
Appears in sequences
- a(n) = (1/(4n-1))*C(4n,2n).at n=9A024491
- Dirichlet convolution of Catalan numbers (1,2,5,14...) with themselves.at n=16A034717
- Third diagonal of array in A059347.at n=33A059348
- 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=17A068875
- Number of fixed points in range [A014137(n-1)..A014138(n-1)] of permutation A089864.at n=36A089408
- Self-convolution of repeated Catalan numbers.at n=33A104722
- 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=16A228403
- a(n) = A241477(n, n).at n=36A241543
- Number of rooted asymmetrical polyenoids of type U_n* having n edges.at n=17A262543
- a(-1)=-1; a(n) = 2*A000108(n) for n >= 0.at n=18A284016
- For any n > 0, let b_n(n+1) = 1, and for k = 1..n, if k divides b_n(k+1) then b_n(k) = b_n(k+1) / k otherwise b_n(k) = b_n(k+1) * k; a(n) = b_n(1).at n=33A374317