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 A132278 Number of distinct terms in rows 1 through n of the triangle of the Narayana numbers (A001263). 0
 1, 1, 2, 3, 5, 7, 10, 13, 17, 21, 26, 31, 37, 43, 49, 56, 64, 72, 81, 90, 100, 110, 121, 132, 144, 156, 169, 182, 196, 210, 225, 240, 256, 272, 289, 306, 324, 342, 361, 380, 400, 420, 441, 462, 484, 506, 529, 552, 575, 599, 624, 649, 675, 701, 728, 755, 783 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS EXAMPLE a(6)=7 because there are 7 distinct terms in the rows 1 through 6 of the triangle of the Narayana numbers: 1; 1,1; 1,3,1; 1,6,6,1; 1,10,20,10,1; 1,15,50,50,15,1. MAPLE seq(nops(`union`(seq({seq(binomial(n, k)*binomial(n, k-1)/n, k=1..n)}, n=1..m))), m=1..57); CROSSREFS Cf. A001263. Sequence in context: A022335 A022780 A075353 * A025700 A033638 A194205 Adjacent sequences:  A132275 A132276 A132277 * A132279 A132280 A132281 KEYWORD nonn AUTHOR Emeric Deutsch, Aug 26 2007 STATUS approved

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Last modified March 29 05:39 EDT 2020. Contains 333105 sequences. (Running on oeis4.)