439600

Appears in sequences

• Number of hierarchical orderings ("societies") of n unlabeled elements ("individuals") with at least two occupied levels.at n=17A110045
• Irregular triangle read by rows: T(n,k) (n >= 1, 0 <= k <= n^2) = number of n X n (0,1) real matrices with k zeros and permanent zero.at n=45A260043