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 A122979 Number of distributive sublattices of the lattice of k-tuples less than the n-th partition (in Abramowitz and Stegun order), that include the maximum element. 3
 2, 4, 7, 8, 21, 45, 16, 58, 84, 200, 500, 32, 152, 293, 748, 1184, 3220 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS After a(18) - for partition [1^5] - the sequence continues ?, 64, 384, 938, 1238, 2520, 5591, ?, ?, ?, ?, ?, 128. LINKS M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy]. EXAMPLE For a(5), partition [2,1], the lattice consists of the 6 pairs (i,j) where 0<=i<=2 and 0<=j<=1, with (i,j) <= (i',j') iff i<=i' and j<=j'. {(2,1), (2,0), (0,1), (0,0)} is one distributive sublattice. CROSSREFS Cf. A122977, A122980, A122981, A036036, A074139. Sequence in context: A013056 A013131 A293759 * A122980 A012985 A291178 Adjacent sequences:  A122976 A122977 A122978 * A122980 A122981 A122982 KEYWORD nonn AUTHOR Franklin T. Adams-Watters, Sep 21 2006 STATUS approved

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Last modified May 5 19:23 EDT 2021. Contains 343573 sequences. (Running on oeis4.)