Skip to content

EvenOddCrank ​

The largest even part minus the number of odd parts.

✓ checked against that system · ! checked, with disagreements (hover a chip)FindStatSt000997via IntegerPartition✓
EvenOddCrank(partition)The largest even part minus the number of odd parts.
Typed signatures
TypePackageApplies
(integer_partition) -> numbercombinatoricsalways

Domain: Partition statistics

Details
  • Defined over IntegerPartition as an expression in _x, evaluated by compute-engine — the definition IS the implementation.
  • Takes a IntegerPartition 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.
  • Not the Andrews-Garvan Crank: this is the largest even part minus the number of odd parts.

Definition

Epsil, as the implementation runs it.

on IntegerPartition, over _x

0 if Length(_x) < 1 else Max(Map(
                                  Function(_x[i] if _x[i] % 2 == 0 else 0, i),
                                  Range(1, Length(_x)),
                                )) - Count(Filter(
                                                  Range(1, Length(_x)),
                                                  Function(_x[i] % 2 == 1, i),
                                                ))

Examples

Basic #

the partition 4+2+14 + 2 + 1 of 77

live ↗
InEvenOddCrank(IntegerPartition⁡([4,2,1]))\mathrm{EvenOddCrank}({\operatorname{IntegerPartition}}([4, 2, 1]))Out33

the partition 3+3+13 + 3 + 1 of 77

live ↗
InEvenOddCrank(IntegerPartition⁡([3,3,1]))\mathrm{EvenOddCrank}({\operatorname{IntegerPartition}}([3, 3, 1]))Out−3-3
Properties #

FindStat's value for [2]

live ↗
InCombinatorialStat(IntegerPartition⁡([2]),EvenOddCrank)\mathrm{CombinatorialStat}({\operatorname{IntegerPartition}}([2]), \text{EvenOddCrank})Out22

Known value · FindStat St000997

FindStat's value for [3]

live ↗
InCombinatorialStat(IntegerPartition⁡([3]),EvenOddCrank)\mathrm{CombinatorialStat}({\operatorname{IntegerPartition}}([3]), \text{EvenOddCrank})Out−1-1

Known value · FindStat St000997

FindStat's value for [4]

live ↗
InCombinatorialStat(IntegerPartition⁡([4]),EvenOddCrank)\mathrm{CombinatorialStat}({\operatorname{IntegerPartition}}([4]), \text{EvenOddCrank})Out44

Known value · FindStat St000997

About
Examples5
CrosswalkFindStat