%I M5300 #28 Jun 01 2022 14:46:07
%S 1,50,887,8790,59542,307960,1301610,4701698,14975675,43025762,
%T 113414717,277904900,639562508,1393844960,2896063220,5768600412,
%U 11066514565,20526933442,36936277875,64660182026,110394412610
%N Antichains (or order ideals) in the poset 2*2*3*n or size of the distributive lattice J(2*2*3*n)
%D J. Berman and P. Koehler, Cardinalities of finite distributive lattices, Mitteilungen aus dem Mathematischen Seminar Giessen, 121 (1976), 103-124.
%D Manfred Goebel, Rewriting Techniques and Degree Bounds for Higher Order Symmetric Polynomials, Applicable Algebra in Engineering, Communication and Computing (AAECC), Volume 9, Issue 6 (1999), 559-573.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H J. Berman and P. Koehler, <a href="/A006356/a006356.pdf">Cardinalities of finite distributive lattices</a>, Mitteilungen aus dem Mathematischen Seminar Giessen, 121 (1976), 103-124. [Annotated scanned copy]
%H G. Kreweras, <a href="http://www.numdam.org/item?id=MSH_1976__53__5_0">Les préordres totaux compatibles avec un ordre partiel</a>, Math. Sci. Humaines No. 53 (1976), 5-30.
%H <a href="/index/Pos#posets">Index entries for sequences related to posets</a>
%F Empirical G.f.: (x+1)*(x^6+36*x^5+279*x^4+594*x^3+279*x^2+36*x+1)/(1-x)^13. [_Colin Barker_, May 29 2012]
%Y Cf. A000217, A000330, A050446, A050447, A006356, A006357, A006358, A006359, A000372, A056932, A006361, A006362, A056933, A056934, A056935, A056936, A056937.
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from _Mitch Harris_, Jul 16 2000