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A085628 Number of antisymmetric transitive binary relations on n labeled points. 1
1, 2, 12, 152, 3504, 135392, 8321472, 784621952, 110521185024, 22789653765632, 6769730814753792, 2859584874712881152, 1699286839524775931904, 1407801166901961190203392, 1613567168628788544015286272, 2541721059997800475952740401152, 5470980000021882982488097199161344 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..16.

G. Pfeiffer, Counting Transitive Relations, preprint, 2004.

FORMULA

a(n) = 2^n * A001035(n) = A000079(n) * A001035(n)

CROSSREFS

Cf. A079265 (unlabeled antisymmetric transitive relations), A001035 (labeled partial orders), A000798 (labeled reflexive transitive relations), A006905 (labeled transitive relations).

Sequence in context: A126345 A208582 A000795 * A177777 A053549 A139383

Adjacent sequences:  A085625 A085626 A085627 * A085629 A085630 A085631

KEYWORD

nonn

AUTHOR

Goetz Pfeiffer (goetz.pfeiffer(AT)nuigalway.ie), Jan 21 2004

EXTENSIONS

2 more terms from Charles R. Greathouse IV Aug 31 2006

STATUS

approved

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Last modified June 19 02:28 EDT 2013. Contains 226385 sequences.