PeakSet from Permutation
The interior positions that rise then fall.
Its size is the Peaks statistic, exactly as DescentSet's is Descents.
Called as CombinatorialMap(x, "PeakSet"). The head's page has its examples.
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Each element of Permutation at a size, and its image, applied in your browser; sizes past 7 are not offered.
Properties
Transport a statistic
Pick a statistic on Finset. Its distribution over the images of Permutation at each size is computed, and compared with the 323 statistics on Permutation: those that share it are the ones the map sends it to, as far as the sizes computed show.
No statistic is declared on Finset.