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 A056937 Number of antichains (or order ideals) in the poset 3*3*3*n or size of the distributive lattice J(3*3*3*n) 8
 1, 980, 211250, 17792748, 781429368, 21238316210, 398925639186, 5585711269074, 61555624183223, 555895303974238, 4242859829536322, 28038281717424550, 163544036697306396, 855242362045150398 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 REFERENCES Berman and Koehler, Cardinalities of finite distributive lattices, Mitteilungen aus dem Mathematischen Seminar Giessen, 121 (1976), p. 103-124 LINKS J. Berman and P. Koehler, Cardinalities of finite distributive lattices, Mitteilungen aus dem Mathematischen Seminar Giessen, 121 (1976), 103-124. [Annotated scanned copy] MATHEMATICA MatrixPower[ ZetaP[ #, n + 1 ][ [ 1, Card[ # ] ] ]&@JofP[ Chain[ 3, 3, 3 ] ] (* This Mathematica program contains undefined functions and at present does not work. *) CROSSREFS Cf. A000372, A006360, A006361, A006362, A056932, A056933, A056934, A056935, A056936. Sequence in context: A188337 A109120 A128483 * A251839 A122472 A252402 Adjacent sequences:  A056934 A056935 A056936 * A056938 A056939 A056940 KEYWORD nonn,easy AUTHOR STATUS approved

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Last modified January 22 12:13 EST 2019. Contains 319363 sequences. (Running on oeis4.)