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 A269736 Triangle read by rows: T(n,r) (0 <= r <= n) = number of idempotents of rank r in the Motzkin monoid M_n. 0
 1, 1, 1, 4, 2, 1, 16, 11, 3, 1, 81, 48, 19, 4, 1, 441, 266, 93, 28, 5, 1, 2601, 1492, 549, 152, 38, 6, 1, 16129, 9042, 3211, 947, 226, 49, 7, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS Table of n, a(n) for n=0..35. I. Dolinka, J. East et al, Idempotent Statistics of the Motzkin and Jones Monoids, arXiv: 1507.04838 (2015), Table 2. EXAMPLE Triangle begins: 1, 1,1, 4,2,1, 16,11,3,1, 81,48,19,4,1, 441,266,93,28,5,1, 2601,1492,549,152,38,6,1, 16129,9042,3211,947,226,49,7,1, ... CROSSREFS First column is A001006(n)^2. Row sums are A256672. Sequence in context: A365566 A326659 A236830 * A264535 A256039 A152391 Adjacent sequences: A269733 A269734 A269735 * A269737 A269738 A269739 KEYWORD nonn,tabl,more AUTHOR N. J. A. Sloane, Mar 13 2016 STATUS approved

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Last modified March 1 08:46 EST 2024. Contains 370430 sequences. (Running on oeis4.)