80821

Appears in sequences

• Number of irreducible posets with n labeled points.at n=6A046908
• Coefficients in the expansion of ([s] + [2s]x + [3s]x^2 + ...)/([r] + [2r]x + [3r]x^2 + ...); [ ] = floor, r = e - 1, s = r/(1-r).at n=34A279632
• 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=22A354615