246295

Appears in sequences

• Number of labeled nonseparable (or 2-connected) bipartite graphs with 2n nodes and n nodes in each part.at n=3A005335
• Triangle read by rows: T(n,k) = number of labeled bicolored nonseparable graphs with k points in one color class and n-k points in the other class. The classes are interchangeable if k = n-k. Here n >= 2, k=1..n-1.at n=24A123474