Skip to content

BicoloredMotzkinLevelSteps ​

The level steps of that bicolored Motzkin path: pairs of steps with one up and one down.

✓ checked against that system · ! checked, with disagreements (hover a chip)FindStatSt001032via DyckPath✓
BicoloredMotzkinLevelSteps(path)The level steps of that bicolored Motzkin path: pairs of steps with one up and one down.
Typed signatures
TypePackageApplies
(dyck_path) -> numbercombinatoricsalways

Domain: Dyck path statistics

Details
  • Defined over DyckPath as an expression in _x, evaluated by compute-engine — the definition IS the implementation.
  • Takes a DyckPath 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 DyckPath, over _x

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

Examples

Basic #

the step word UUDDUDUUDDUD

live ↗
InBicoloredMotzkinLevelSteps(DyckPath⁡([1,1,0,0,1,0]))\mathrm{BicoloredMotzkinLevelSteps}({\operatorname{DyckPath}}([1, 1, 0, 0, 1, 0]))Out11

the step word UDUUDDUDUUDD

live ↗
InBicoloredMotzkinLevelSteps(DyckPath⁡([1,0,1,1,0,0]))\mathrm{BicoloredMotzkinLevelSteps}({\operatorname{DyckPath}}([1, 0, 1, 1, 0, 0]))Out11
Properties #

FindStat's value for [1,0,1,0]

live ↗
InCombinatorialStat(DyckPath⁡([1,0,1,0]),BicoloredMotzkinLevelSteps)\mathrm{CombinatorialStat}({\operatorname{DyckPath}}([1, 0, 1, 0]), \text{BicoloredMotzkinLevelSteps})Out22

Known value · FindStat St001032

FindStat's value for [1,1,0,0]

live ↗
InCombinatorialStat(DyckPath⁡([1,1,0,0]),BicoloredMotzkinLevelSteps)\mathrm{CombinatorialStat}({\operatorname{DyckPath}}([1, 1, 0, 0]), \text{BicoloredMotzkinLevelSteps})Out00

Known value · FindStat St001032

FindStat's value for [1,0,1,0,1,0]

live ↗
InCombinatorialStat(DyckPath⁡([1,0,1,0,1,0]),BicoloredMotzkinLevelSteps)\mathrm{CombinatorialStat}({\operatorname{DyckPath}}([1, 0, 1, 0, 1, 0]), \text{BicoloredMotzkinLevelSteps})Out33

Known value · FindStat St001032

About
Examples5
CrosswalkFindStat