300830572
domain: N
Appears in sequences
- a(n) = binomial(3*n,n)/(2*n+1) (enumerates ternary trees and also noncrossing trees).at n=13A001764
- If n = 2*m then a(n) = binomial(3*m, m)/(2*m+1), if n=2*m+1 then a(n) = binomial(3*m+1, m+1)/(2*m+1).at n=26A047749
- Number of dissectable polyhedra with n tetrahedral cells and symmetry of type F.at n=50A047760
- a(n) = A047760(2n+1).at n=25A047761
- Number of dissectable polyhedra with n tetrahedral cells and symmetry of type P.at n=51A047765
- a(n) = A047765(2n).at n=25A047767
- Interpolation of A001764(n+1) and A006629(n).at n=24A124817
- Expansion of series reversion of generating function for triangular numbers.at n=13A179848
- Terms of A001764 not divisible by 3, where A001764 enumerates ternary trees.at n=3A201823