%I A006982 M0700
%S A006982 1,1,1,1,2,3,5,8,15,26,47,82,151,269,494,891,1639,2978,5483,10006,18428,
33749,62162,114083,210189,386292,711811,1309475,2413144,4442221,
%T A006982 8186962,15077454,27789108,51193086,94357143,173859936,320462062,590555664,
1088548290,2006193418,3697997558,6815841849,12563729268,23157428823,
%U A006982 42686759863,78682454720,145038561665,267348052028,492815778109,908414736485
%N A006982 Number of unlabeled distributive lattices with n elements.
%D A006982 J. Heitzig and J. Reinhold, Counting finite lattices, Algebra Universalis,
48 (2002), 43-53.
%D A006982 J. Heitzig and J. Reinhold, The number of unlabeled orders on fourteen
elements, Order 17 (2000) no. 4, 333-341.
%D A006982 P. D. Lincoln, personal communication.
%D A006982 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences,
Academic Press, 1995 (includes this sequence).
%H A006982 J. Heitzig and J. Reinhold, <a href="http://www-ifm.math.uni-hannover.de/
forschung/preprintsifm.html">Counting finite lattices</a>, preprint
no. 298, Institut fuer Mathematik, Universitaet Hanover, Germany,
1999.
%H A006982 M. Erne, J. Heitzig and J. Reinhold, On the number of distributive lattices,
<a href="http://www.combinatorics.org/">Electronic Journal of Combinatorics</
a>, 9 (2002), #R24.
%H A006982 Institut f. Mathematik, Univ. Hanover, <a href="http://www-ifm.math.uni-hannover.de/
html/preprints.phtml">Erne/Heitzig/Reinhold papers</a>
%Y A006982 Cf. A006981, A006966.
%Y A006982 Sequence in context: A058519 A151518 A082095 this_sequence A054539 A026702
A000047
%Y A006982 Adjacent sequences: A006979 A006980 A006981 this_sequence A006983 A006984
A006985
%K A006982 hard,nonn,nice
%O A006982 0,5
%A A006982 N. J. A. Sloane (njas(AT)research.att.com).
%E A006982 More terms from Jobst Heitzig (heitzig(AT)math.uni-hannover.de), Feb
02 2001. These were computed by the same algorithm that was used
to enumerate the posets on 14 elements.
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