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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

Table of n, a(n) for n=1..57.

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 May 23 07:54 EDT 2019. Contains 323508 sequences. (Running on oeis4.)