A267391 Number of elements of S_n with strategic pile of size 5.

0, 0, 0, 0, 0, 40, 240, 1980, 18240

Offset

1,6

Comments

Strategic pile is defined in A267323.

Links

Table of n, a(n) for n=1..9.

K. L. M. Adamyk, E. Holmes, G. R. Mayfield, D. J. Moritz, M. Scheepers, B. E. Tenner, H. C. Wauck, Sorting Permutations: Games, Genomes, and Cycles, arXiv:1410.2353 [math.CO], 2014-2017.

Marisa Gaetz, Bethany Flanagan, Marion Scheepers, Meghan Shanks, Quantifying CDS Sortability of Permutations by Strategic Pile Size, arXiv:1811.11937 [math.CO], 2018.

Example

P = [7, 1, 5, 6, 2, 4, 3] has strategic pile size 5. The composition (0,3,4,2,6,5,1,7)(0,1,2,3,4,5,6,7) has cycle (7,3,2,4,1,6,0), and so the strategic pile of P is {1,2,3,4,6}.

Crossrefs

A267323 gives the corresponding sequence for strategic piles of size 3.

A267324 gives the corresponding sequence for strategic piles of size 4.

Sequence in context: A235885 A068790 A073962 * A229632 A223426 A290127

Adjacent sequences: A267388 A267389 A267390 * A267392 A267393 A267394

Keyword

nonn,more

Author

Marion Scheepers, Jan 13 2016

Status

approved