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# descendingRuns -- computes the descending runs of a permutation

- Usage:
    `descendingRuns w`
- Inputs:
  - w, a permutation,
- Outputs:
  - allRuns, a list,

## Description

A descending run is a maximal subsequence of successive descents.

    i1 : p = permutation {3,1,2,5,4}

    o1 = Permutation{3, 1, 2, 5, 4}

    o1 : Permutation

    i2 : descendingRuns p

    o2 = {(3, 1), 1 : (2), (5, 4)}

    o2 : List

## See also

- ascendingRuns -- computes the ascending runs of a permutation
- ascents -- computes the ascents of a permutation
- descents -- computes the descents of a permutation
- exceedances -- computes the exceedances of a permutation
- saliances -- computes the saliances of a permutation
- records -- computes the saliances of a permutation

## Ways to use descendingRuns:

- `descendingRuns(Permutation)`

## For the programmer

The object descendingRuns is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/Permutations/Documentation/mainDocs.m2:158:0.