%I #60 Nov 19 2024 05:24:00
%S 1,1,4,12,47,174,749,3291,15675,78104,411042,2261961,13009112,77860234
%N Number of partially ordered sets with no isolated points and with n "lines": pairs (a,b) where a < b and there is no c with a < c < b. The lines form the minimal basis for the partial ordering.
%C The points are unlabeled.
%D See A000112 for references and links about partially ordered sets.
%H N. J. A. Sloane, <a href="/A022016/a022016.jpg">Illustration of initial terms of A022016 and A022017</a>.
%e See Sloane's link.
%Y Cf. A000112, A022017, A342447.
%K nonn,more,changed
%O 0,3
%A _Franklin T. Adams-Watters_, Mar 30 2002
%E a(6)-a(13) from Rico Zöllner and _Konrad Handrich_, Nov 19 2024