0,5

J. A. Wright, There are 718 6-point topologies, quasi-orderings and transgraphs, Notices Amer. Math. Soc., 17 (1970), p. 646, Abstract #70T-A106.

S. R. Finch, Series-parallel networks

Index entries for sequences related to posets

A003431 gives isomorphism classes of these posets.

Sequence in context: A129622 A112011 A112010 this_sequence A130552 A160260 A114051

Adjacent sequences: A046903 A046904 A046905 this_sequence A046907 A046908 A046909

nonn

John A. Wright.