%I #7 Mar 16 2021 08:30:18
%S 6,108,2310,65700,2583126,142259628,11012710470,1196543891700,
%T 181782466114326,38435786111785788,11256358984173551430
%N Number of labeled order relations on n nodes in which longest chain has 3 nodes.
%D L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 60.
%Y A column or diagonal of triangle in A342587.
%K nonn
%O 3,1
%A _N. J. A. Sloane_, Jul 10 2000
%E Extended to n=13 by _Brendan McKay_, Mar 16 2021