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 A151338 Triangle read by rows: T(n,k) = number of partitions of [1..k] into n nonempty clumps of sizes 1, 2, 3, 4 or 5 (n >= 0, 0 <= k <= 5n). 4
 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 3, 7, 15, 31, 56, 91, 126, 126, 0, 0, 0, 1, 6, 25, 90, 301, 938, 2737, 7455, 18711, 41811, 81081, 126126, 126126, 0, 0, 0, 0, 1, 10, 65, 350, 1701, 7686, 32725, 132055, 505351, 1824823, 6173167, 19339320, 55096041 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,11 COMMENTS Row n has 5n+1 entries. LINKS Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, Analysis of the Gift Exchange Problem, arXiv:1701.08394, 2017. David Applegate and N. J. A. Sloane, The Gift Exchange Problem (arXiv:0907.0513, 2009) EXAMPLE The triangle begins: 1 0, 1, 1, 1, 1, 1 0, 0, 1, 3, 7, 15, 31, 56, 91, 126, 126 0, 0, 0, 1, 6, 25, 90, 301, 938, 2737, 7455, 18711, 41811, 81081, 126126, 126126 0, 0, 0, 0, 1, 10, 65, 350, 1701, 7686, 32725, 132055, 505351, 1824823, 6173167, 19339320, 55096041, 138654516, 295891596, 488864376, 488864376 0, 0, 0, 0, 0, 1, 15, 140, 1050, 6951, 42315, 241780, 1310925, 6782776, 33549516, 158533375, 713733020, 3046944901, 12246267033, 45892143297, 158167994985, 491492022021, 1336310771796, 3030225834636, 5194672859376, 5194672859376 ... CROSSREFS This is one of a sequence of triangles: A144331, A144385, A144643, A151338, A151359, ... See A151509, A151510 for other versions. Sequence in context: A137170 A222813 A304078 * A229006 A023424 A276647 Adjacent sequences: A151335 A151336 A151337 * A151339 A151340 A151341 KEYWORD nonn,tabf AUTHOR N. J. A. Sloane, May 13 2009 STATUS approved

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Last modified January 27 19:27 EST 2023. Contains 359846 sequences. (Running on oeis4.)