A038002 Number of connected functions on n points with a single labeled point.
0, 1, 3, 9, 27, 81, 242, 722, 2150, 6395, 19003, 56428, 167458, 496724, 1472835, 4365692, 12936998, 38327764, 113529027, 336221554, 995586119, 2947641940, 8726093434, 25829729702, 76450357119, 226257478851, 669566448376, 1981320898874, 5862583555761
Offset: 0
Keywords
Links
- Alois P. Heinz, Table of n, a(n) for n = 0..1000
Formula
G.f.: B(x)(B(x)+1) where B(x) is g.f. of A000107.
a(n) = Sum_{k=1..n} k * A339067(n,k). - Alois P. Heinz, Dec 04 2020
G.f.: A000081(x) / (1 - A000081(x))^2, where A000081(x) is the g.f. of A000081. - Vaclav Kotesovec, Jan 03 2021