Search: id:A000112 Results 1-1 of 1 results found. %I A000112 M1495 N0588 %S A000112 1,1,2,5,16,63,318,2045,16999,183231,2567284,46749427,1104891746, %T A000112 33823827452,1338193159771,68275077901156,4483130665195087 %N A000112 Number of partially ordered sets ("posets") with n unlabeled elements. %C A000112 Also fixed effects ANOVA models with n factors, which may be both crossed and nested. %C A000112 [ a(15)-a(16) are from Brinkmann's and McKay's paper ] - Vladeta Jovovic (vladeta(AT)eunet.rs), Jan 04 2006 %D A000112 G. Birkhoff, Lattice Theory, 1961, p. 4. %D A000112 C. Chaunier and N. Lygeros, Progres dans l'enumeration des posets, C. R. Acad. Sci. Paris 314 serie I (1992) 691-694. %D A000112 C. Chaunier and N. Lygeros, The Number of Orders with Thirteen Elements, Order 9:3 (1992) 203-204. %D A000112 C. Chaunier and N. Lygeros, Le nombre de posets a isomorphie pres ayant 12 elements. Theoretical Computer Science, 123 p. 89-94, 1994. %D A000112 L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 60. %D A000112 R. Fraisse and N. Lygeros, Petits posets: denombrement, representabilite par cercles et compenseurs. C. R. Acad. Sci. Paris, 313, I, 417-420, 1991. %D A000112 D. J. Kleitman and B. L. Rothschild, Asymptotic enumeration of partial orders on a finite set, Trans. Amer. Math. Soc., 205 (1975) 205-220. %D A000112 N. Lygeros, Calculs exhaustifs sur les posets d'au plus 7 elements. SINGULARITE, vol. 2 n4 p. 10-24, avril 1991. %D A000112 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A000112 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A000112 R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 1, Chap. 3, pages 96ff; Vol. 2, Problem 5.39, p. 88. %D A000112 For further references concerning the enumeration of topologies and posets see under A001035. %H A000112 David Wasserman, Table of n, a(n) for n = 0..16 %H A000112 R. Bayon, N. Lygeros and J.-S. Sereni, New progress in enumeration of mixed models, Applied Mathematics E-Notes, 5 (2005), 60-65. %H A000112 R. Bayon, N. Lygeros and J.-S. Sereni, Nouveaux progr\`es dans l'\'enum\'eration des mod\`eles mixtes, in Knowledge discovery and discrete mathematics : JIM'2003, INRIA, Universit\'e de Metz, France, 2003, pp. 243-246. %H A000112 Gunnar Brinkmann and Brendan D. McKay, Counting unlabeled topologies and transitive relations. %H A000112 P. J. Cameron, Sequences realized by oligomorphic permutation groups, J. Integ. Seqs. Vol. 3 (2000), #00.1.5. %H A000112 S. R. Finch, Transitive relations, topologies and partial orders %H A000112 Ann Marie Hess, Mixed Models Site %H A000112 N. Lygeros and P. Zimmermann, Computation of P(14), the number of posets with 14 elements: 1.338.193.159.771 %H A000112 G. Pfeiffer, Counting Transitive Relations, Journal of Integer Sequences, Vol. 7 (2004), Article 04.3.2. %H A000112 Bob Proctor, Chapel Hill Poset Atlas %H A000112 D. Rusin, Further information and references %H A000112 N. J. A. Sloane, Classic Sequences %H A000112 Index entries for sequences related to posets %H A000112 Index entries for "core" sequences %e A000112 R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 1, Chap. 3, page 98, Fig. 3-1 shows the unlabeled posets with <= 4 points. %Y A000112 Cf. A000798 (labeled topologies), A001035 (labeled posets), A001930 (unlabeled topologies), A006057. %Y A000112 Cf. A079263, A079265. %Y A000112 Sequence in context: A111004 A079566 A059685 this_sequence A127083 A131178 A003149 %Y A000112 Adjacent sequences: A000109 A000110 A000111 this_sequence A000113 A000114 A000115 %K A000112 nonn,hard,core,nice %O A000112 0,3 %A A000112 N. J. A. Sloane (njas(AT)research.att.com). %E A000112 More terms from Vladeta Jovovic (vladeta(AT)eunet.rs), Jan 04 2006, corrected Jan 15 2006 Search completed in 0.002 seconds