A055532 Number of labeled order relations on n nodes in which longest chain has 3 nodes.

6, 108, 2310, 65700, 2583126, 142259628, 11012710470, 1196543891700, 181782466114326, 38435786111785788, 11256358984173551430

Offset: 3

Author

N. J. A. Sloane, Jul 10 2000

Keywords

• nonn

References

• L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 60.

Crossrefs

A column or diagonal of triangle in A342587.

Extensions

Extended to n=13 by Brendan McKay, Mar 16 2021