549342

Appears in sequences

• Triangle read by rows: T(n,k) is the number of hex trees with n edges and k pairs of adjacent vertices of outdegree 2.at n=22A126188
• Number of hex trees with n edges and no adjacent vertices of outdegree 2.at n=10A126189
• Number of Dyck paths with no UUU's and no DDD's, of semilength n and having no UDUD's (U=(1,1), D=(1,-1)).at n=26A166289