12233141908
domain: N
Appears in sequences
- a(n) = C_n / 2 if n is even or ( C_n + C_((n-1)/2) ) / 2 if n is odd, where C = Catalan numbers (A000108).at n=20A007595
- Number of plane trees with n edges and having an odd number of leaves.at n=20A071684
- Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A089864.at n=21A089402
- Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A069772.at n=21A089880