LeftToRightMaximaXorRightToLeftMinima on Permutation

Positions that are a left-to-right maximum or a right-to-left minimum but not both.

On Permutation

Called as CombinatorialStat(x, "LeftToRightMaximaXorRightToLeftMinima"). The head's page has its examples.

Live

Distribution

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Sizes 1 to

FindStat St001005

The number of indices for a permutation that are either left-to-right maxima or right-to-left minima but not both.

Object	Value
[1,2]	0
[2,1]	2
[1,2,3]	0
[1,3,2]	2
[2,1,3]	2
[2,3,1]	3
[3,1,2]	3
[3,2,1]	2

Data from FindStat, the combinatorial statistic finder; the page at findstat.org/St001005 has the rest.