1335600

Appears in sequences

• Number of arrangements on a line of n finite closed intervals (possibly of zero length) with k distinct endpoints (n >= 1, 1 <= k <= 2*n).at n=26A300729
• Triangular array read by rows: T(n,k) is the number of labeled posets on [n] that are composed of exactly k irreducible posets, n >= 0, 0 <= k <= n.at n=41A354615