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A091073
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Number of transitive relations on n unlabeled points.
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4
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1, 2, 8, 39, 242, 1895, 19051, 246895, 4145108, 90325655, 2555630036, 93810648902, 4461086120602, 274339212258846, 21775814889230580, 2226876304576948549
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OFFSET
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0,2
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COMMENTS
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a(13)-a(15) are from Brinkmann's and McKay's paper. - Vladeta Jovovic, Jan 07 2006
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LINKS
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CROSSREFS
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Cf. A079265 (antisymmetric transitive relations), A001930 (reflexive transitive relations), A000112 (partial orders), A006905 (labeled transitive relations).
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KEYWORD
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hard,nonn,nice
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AUTHOR
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Goetz Pfeiffer (goetz.pfeiffer(AT)nuigalway.ie), Jan 21 2004
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EXTENSIONS
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STATUS
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approved
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