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A144402 Triangle in A144385 read downwards by columns. 3
1, 0, 1, 0, 1, 1, 0, 1, 3, 1, 0, 0, 7, 6, 1, 0, 0, 10, 25, 10, 1, 0, 0, 10, 75, 65, 15, 1, 0, 0, 0, 175, 315, 140, 21, 1, 0, 0, 0, 280, 1225, 980, 266, 28, 1, 0, 0, 0, 280, 3780, 5565, 2520, 462, 36, 1, 0, 0, 0, 0, 9100, 26145, 19425, 5670, 750, 45, 1, 0, 0, 0, 0, 15400 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,9

COMMENTS

The Bell transform of the sequence "g(n) = 1 if n<3 else 0". For the definition of the Bell transform see A264428. - Peter Luschny, Jan 19 2016

LINKS

Table of n, a(n) for n=0..70.

Moa Apagodu, David Applegate, N. J. A. Sloane, and Doron Zeilberger, Analysis of the Gift Exchange Problem, arXiv:1701.08394 [math.CO], 2017.

David Applegate and N. J. A. Sloane, The Gift Exchange Problem, arXiv:0907.0513 [math.CO], 2009.

MATHEMATICA

BellMatrix[f_Function, len_] := With[{t = Array[f, len, 0]}, Table[BellY[n, k, t], {n, 0, len-1}, {k, 0, len-1}]];

rows = 12;

M = BellMatrix[If[#<3, 1, 0]&, rows];

Table[M[[n, k]], {n, 1, rows}, {k, 1, n}] // Flatten (* Jean-Fran├žois Alcover, Jul 14 2018, after Peter Luschny *)

PROG

(Sage) # uses[bell_matrix from A264428]

bell_matrix(lambda n: 1 if n<3 else 0, 12) # Peter Luschny, Jan 19 2016

CROSSREFS

Cf. A111246.

Sequence in context: A110517 A091925 A034370 * A264429 A324163 A127537

Adjacent sequences:  A144399 A144400 A144401 * A144403 A144404 A144405

KEYWORD

nonn,tabl

AUTHOR

David Applegate and N. J. A. Sloane, Dec 07 2008

STATUS

approved

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Last modified July 31 20:24 EDT 2021. Contains 346377 sequences. (Running on oeis4.)