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A144645 Triangle in A144643 read upwards by columns. 1
1, 1, 0, 1, 1, 0, 1, 3, 1, 0, 1, 6, 7, 1, 0, 1, 10, 25, 15, 0, 0, 1, 15, 65, 90, 25, 0, 0, 1, 21, 140, 350, 280, 35, 0, 0, 1, 28, 266, 1050, 1645, 770, 35, 0, 0, 1, 36, 462, 2646, 6825, 6930, 1855, 0, 0, 0, 1, 45, 750, 5880, 22575, 39795, 26425, 3675, 0, 0, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,8

LINKS

Table of n, a(n) for n=0..66.

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

David Applegate and N. J. A. Sloane, The Gift Exchange Problem (arXiv:0907.0513, 2009)

EXAMPLE

Triangle begins:

1

1,0

1,1,0

1,3,1,0

1,6,7,1,0

1,10,25,15,0,0

1,15,65,90,25,0,0

1,21,140,350,280,35,0,0

1,28,266,1050,1645,770,35,0,0

1,36,462,2646,6825,6930,1855,0,0,0

1,45,750,5880,22575,39795,26425,3675,0,0,0

CROSSREFS

Sequence in context: A256551 A144417 A085791 * A151510 A151512 A106800

Adjacent sequences:  A144642 A144643 A144644 * A144646 A144647 A144648

KEYWORD

nonn,tabl

AUTHOR

David Applegate and N. J. A. Sloane, Jan 25 2009

STATUS

approved

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Last modified June 1 07:40 EDT 2020. Contains 334759 sequences. (Running on oeis4.)