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LongestAscent ​

The longest run of consecutive up steps.

✓ checked against that system · ! checked, with disagreements (hover a chip)FindStatSt000444via DyckPath✓
LongestAscent(path)The longest run of consecutive up steps.
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 Fold(Function(
                                        [Max([a[1], a[2] + 1]), a[2] + 1] if b ==
                                                                             1 else [a[1], 0],
                                        a,
                                        b,
                                      ), [0, 0], _x)[1]

Examples

Basic #

the step word UUDDUDUUDDUD

live ↗
InLongestAscent(DyckPath⁡([1,1,0,0,1,0]))\mathrm{LongestAscent}({\operatorname{DyckPath}}([1, 1, 0, 0, 1, 0]))Out22

the step word UDUUDDUDUUDD

live ↗
InLongestAscent(DyckPath⁡([1,0,1,1,0,0]))\mathrm{LongestAscent}({\operatorname{DyckPath}}([1, 0, 1, 1, 0, 0]))Out22
Properties #

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

live ↗
InCombinatorialStat(DyckPath⁡([1,0,1,0]),LongestAscent)\mathrm{CombinatorialStat}({\operatorname{DyckPath}}([1, 0, 1, 0]), \text{LongestAscent})Out11

Known value · FindStat St000444

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

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

Known value · FindStat St000444

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

live ↗
InCombinatorialStat(DyckPath⁡([1,0,1,0,1,0]),LongestAscent)\mathrm{CombinatorialStat}({\operatorname{DyckPath}}([1, 0, 1, 0, 1, 0]), \text{LongestAscent})Out11

Known value · FindStat St000444

About
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