A224181 Number of permutations of length n containing exactly 2 occurrences of 1243.

0, 0, 0, 0, 4, 56, 543, 4600, 36691, 284370, 2174352, 16533360, 125572259, 955035260, 7283925999, 55755366698, 428521485446, 3307587704256, 25640569219948, 199621168997272, 1560661865377319, 12251246212162453, 96551383368363609, 763795078132240253

Offset

1,5

Links

Table of n, a(n) for n=1..24.

Andrew R. Conway and Anthony J. Guttmann, Counting occurrences of patterns in permutations, arXiv:2306.12682 [math.CO], 2023. See p. 21.

Brian Nakamura, Approaches for enumerating permutations with a prescribed number of occurrences of patterns, PU. M. A. 24 (2013), 179-194.

Brian Nakamura, Approaches for enumerating permutations with a prescribed number of occurrences of patterns, arXiv 1301.5080 [math.CO], 2013.

Maple

Programs can be obtained from the arXiv 1301.5080 link.

Crossrefs

Sequence in context: A020540 A101540 A358882 * A026740 A191466 A333294

Adjacent sequences: A224178 A224179 A224180 * A224182 A224183 A224184

Keyword

nonn

Author

Brian Nakamura, Apr 01 2013

Status

approved