1479786

Appears in sequences

• Triangle read by rows: T(n,k) (n >= 2, k >= 1) is the number of non-crossing connected graphs on n nodes on a circle such that the distance from a fixed node (root) to the next node is k. Rows are indexed 2,3,4,...; columns are indexed 1,2,3, ... .at n=37A143018
• Sum of the root degrees over all non-crossing connected graphs on n nodes on a circle (by root we mean a distinguished node).at n=7A143023