183594

Appears in sequences

• Triangle read by rows: T(n,k) is the number of ordered trees with n edges and having k vertices of outdegree 2 that have (two) leaves as their (two) children.at n=43A178519
• a(n) = 5*a(n-1) + 2*5^n - 1, a(0) = 0.at n=6A392137