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A168256 Triangle read by rows: Catalan number C(n) repeated n+1 times. 1
1, 1, 1, 2, 2, 2, 5, 5, 5, 5, 14, 14, 14, 14, 14, 42, 42, 42, 42, 42, 42, 132, 132, 132, 132, 132, 132, 132, 429, 429, 429, 429, 429, 429, 429, 429, 1430, 1430, 1430, 1430, 1430, 1430, 1430, 1430, 1430, 4862, 4862, 4862, 4862, 4862, 4862, 4862, 4862, 4862, 4862 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

As square array, it is A x B where A = square array A039599 (completed with zeros) and B = transpose of A. - Philippe Deléham, May 22 2015

LINKS

Table of n, a(n) for n=0..54.

FORMULA

T(n,k) = A000108(n). - R. J. Mathar, Nov 03 2016

G.f.: (x*C(x)-x*y*C(x*y))/(x-x*y), where C(x) is the g.f. of A000108. - Vladimir Kruchinin, Nov 19 2020

EXAMPLE

Triangle begins:

  1;

  1, 1;

  2, 2, 2;

  5, 5, 5, 5 ;

  14, 14, 14, 14, 14;

  42, 42, 42, 42, 42, 42;

From Philippe Deléham, May 22 2015: (Start)

A = square array A039599, completed with zeros.

  1.....0.....0.....0...

  1.....1.....0.....0...

  2.....3.....1.....0...

  5.....9.....5.....1...

  ......................

B = transpose of A.

  1.....1.....2.....5...

  0.....1.....3.....9...

  0.....0.....1.....5...

  0.....0.....0.....1...

  ......................

A x B = this sequence read as square array.

  1.....1.....2.....5...

  1.....2.....5....14...

  2.....5....14....42...

  5....14....42...132...

  ...................... (End)

CROSSREFS

Cf. A000108, A000984 (row sums), A039599, A172414.

Sequence in context: A346426 A105960 A081290 * A123081 A020917 A308772

Adjacent sequences:  A168253 A168254 A168255 * A168257 A168258 A168259

KEYWORD

nonn,tabl,easy

AUTHOR

Mark Dols, Nov 21 2009

STATUS

approved

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Last modified August 1 14:14 EDT 2021. Contains 346391 sequences. (Running on oeis4.)