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A127124 Number of endofunctions whose component sizes form the n-th partition in Mathematica order. 1
1, 1, 2, 1, 4, 2, 1, 9, 4, 3, 2, 1, 20, 9, 8, 4, 3, 2, 1, 51, 20, 18, 9, 10, 8, 4, 4, 3, 2, 1, 125, 51, 40, 20, 36, 18, 9, 10, 12, 8, 4, 4, 3, 2, 1, 329, 125, 102, 51, 80, 40, 20, 45, 36, 27, 18, 9, 20, 10, 12, 8, 4, 5, 4, 3, 2, 1, 862, 329, 250, 125, 204, 102, 51, 180, 80, 60, 40, 20, 45 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Can be regarded as a triangle with one row for each size of partition.

LINKS

Table of n, a(n) for n=0..79.

EXAMPLE

For n = 3, the 7 endofunctions are (1,2,3) -> (1,1,1), (1,1,2), (1,2,1), (2,1,1), (1,2,3), (1,3,2) and (2,3,1). The components are respectively 123, 123, 13|2, 123, 1|2|3, 1|23 and 123, corresponding to partitions [3], [3], [2,1], [3], [1^3], [2,1] and [3]. The partitions of 3 in Mathematica order are [3], [2,1] and [1^3], so row 3 is 4,2,1.

The triangle starts:

1

1

2 1

4 2 1

9 4 3 2 1

20 9 8 4 3 2 1

CROSSREFS

Sequence in context: A158264 A274106 A158982 * A127136 A239101 A145983

Adjacent sequences:  A127121 A127122 A127123 * A127125 A127126 A127127

KEYWORD

nonn,tabf

AUTHOR

Franklin T. Adams-Watters, Jan 05 2007

STATUS

approved

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Last modified April 20 04:42 EDT 2019. Contains 322294 sequences. (Running on oeis4.)