Skip to content

NormalizedSumOfDistancesToGreaterElement ​

The same sum, each gap one less: the entries strictly between a position and its nearest greater entry.

✓ checked against that system · ! checked, with disagreements (hover a chip)FindStatSt000624via Permutation✓
NormalizedSumOfDistancesToGreaterElement(p)The same sum, each gap one less: the entries strictly between a position and its nearest greater entry.
Typed signatures
TypePackageApplies
(permutation) -> numbercombinatoricsalways

Domain: Permutation statistics

Details
  • Defined over Permutation as an expression in _x, evaluated by compute-engine — the definition IS the implementation.
  • Takes a Permutation and nothing else — it reads values against their positions, or walks the orbits, so it needs the bijection. Applying it to a bare list is a type error, not a wrong answer.

Definition

Epsil, as the implementation runs it.

on Permutation, over _x

0 if Length(_x) < 1 else Sum(Map(Function(Min(Join(
                                                    [i, Length(_x) + 1 - i],
                                                    Map(
                                                         Function(Abs(j - i), j),
                                                         Filter(
                                                                 Range(
                                                                        1,
                                                                        Length(_x),
                                                                      ),
                                                                 Function(_x[j] >
                                                                          _x[i], j),
                                                               ),
                                                       ),
                                                  )) - 1, i), Range(
                                                                    1,
                                                                    Length(_x),
                                                                  )))

Examples

Basic #

the one-line word 312312

live ↗
InNormalizedSumOfDistancesToGreaterElement(Permutation⁡([3,1,2]))\mathrm{NormalizedSumOfDistancesToGreaterElement}({\operatorname{Permutation}}([3, 1, 2]))Out00

the one-line word 24132413

live ↗
InNormalizedSumOfDistancesToGreaterElement(Permutation⁡([2,4,1,3]))\mathrm{NormalizedSumOfDistancesToGreaterElement}({\operatorname{Permutation}}([2, 4, 1, 3]))Out11
Properties #

FindStat's value for [1,2]

live ↗
InCombinatorialStat(Permutation⁡([1,2]),NormalizedSumOfDistancesToGreaterElement)\mathrm{CombinatorialStat}({\operatorname{Permutation}}([1, 2]), \text{NormalizedSumOfDistancesToGreaterElement})Out00

Known value · FindStat St000624

FindStat's value for [2,1]

live ↗
InCombinatorialStat(Permutation⁡([2,1]),NormalizedSumOfDistancesToGreaterElement)\mathrm{CombinatorialStat}({\operatorname{Permutation}}([2, 1]), \text{NormalizedSumOfDistancesToGreaterElement})Out00

Known value · FindStat St000624

FindStat's value for [1,2,3]

live ↗
InCombinatorialStat(Permutation⁡([1,2,3]),NormalizedSumOfDistancesToGreaterElement)\mathrm{CombinatorialStat}({\operatorname{Permutation}}([1, 2, 3]), \text{NormalizedSumOfDistancesToGreaterElement})Out00

Known value · FindStat St000624

About
Examples5
CrosswalkFindStat