161406

Appears in sequences

• Number of labeled digraphs where every node has indegree 0 or outdegree 0 and no isolated nodes.at n=7A052332
• Number of labeled bipartite graphs on n vertices with no isolated vertices.at n=7A122802
• Triangle T(n,k) read by rows: T(n, k) = (m*n - m*k + 1)*T(n - 1, k - 1) + (5*k - 4)*(m*k - (m - 1))*T(n - 1, k) where m = 0.at n=41A166973
• Triangle T(n,k) of strongly graded (3+1)-free partially ordered sets (posets) on n labeled vertices with height k.at n=22A222864
• Numbers that divide the sum of the reverse of their divisors (A069192).at n=14A254008
• Triangle read by rows: T(n,k) is the number of labeled tiered posets with n elements and height k.at n=30A361956