ProjectivesOfInjectiveDimensionAtMostDominantDimension

The indecomposable projective modules whose injective dimension is at most their dominant dimension.

✓ checked against that system · ! checked, with disagreements (hover a chip)FindStatSt000998via DyckPath✓↗

ProjectivesOfInjectiveDimensionAtMostDominantDimension(path)The indecomposable projective modules whose injective dimension is at most their dominant dimension.

Typed signatures

Type	Package	Applies
(dyck_path) -> number	combinatorics	always

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.
• FindStat's St000998, read with the dominant dimension of the module itself: that is the reading its rows follow.

Definition

Epsil, as the implementation runs it.

on DyckPath, over _x

0 if Length(_x) < 1 else Apply(
                                (series: list<integer>) => Apply(
                                                                  (projectiveInjectiveDims: list<integer>) => Apply(
                                                                                                                     (projectiveDominantDims: list<integer>) => Count(Filter(Range(1, Length(_x) / 2 +
                                                                                                                                                                                      1), Function(projectiveInjectiveDims[v] <= projectiveDominantDims[v], v))),
                                                                                                                     Map(Function(Fold(
                                                                                                                                        Function(Apply((socle: integer) => Apply(
                                                                                                                                                                                  (hull: integer) => Apply(
                                                                                                                                                                                                            (flag: integer) => [a[1], 0, a[3] + flag, flag] if a[2] == 0 else [hull, a[1] - hull, a[3] + flag, flag],
                                                                                                                                                                                                            a[4] *
                                                                                                                                                                                                            (1 if a[2] == 0 ||
                                                                                                                                                                                                                  series[hull + 1] ==
                                                                                                                                                                                                                  socle + 1 -
                                                                                                                                                                                                                  hull else 0),
                                                                                                                                                                                                          ),
                                                                                                                                                                                  Min(Filter(
                                                                                                                                                                                              Range(0, socle, 1),
                                                                                                                                                                                              Function(x +
                                                                                                                                                                                                       series[x + 1] >
                                                                                                                                                                                                       socle, x),
                                                                                                                                                                                            )),
                                                                                                                                                                                ), Max(a[1] + a[2] -
                                                                                                                                                                                      1, 0)), a, b),
                                                                                                                                        [v - 1, series[v], 0, 1],
                                                                                                                                        Range(1, Length(_x) / 2 +
                                                                                                                                                 1),
                                                                                                                                      )[3], v), Range(1, Length(_x) / 2 +
                                                                                                                                                        1)),
                                                                                                                   ),
                                                                  Map(
                                                                       Function(Fold(
                                                                                      Function(Apply(
                                                                                                      (socle: integer) => Apply(
                                                                                                                                 (hull: integer) => [a[1], a[2], a[3]] if a[1] == hull else [hull, a[1] - hull, a[3] + 1],
                                                                                                                                 Min(Filter(
                                                                                                                                             Range(0, socle, 1),
                                                                                                                                             Function(x +
                                                                                                                                                      series[x + 1] >
                                                                                                                                                      socle, x),
                                                                                                                                           )),
                                                                                                                               ),
                                                                                                      a[1] + a[2] -
                                                                                                      1,
                                                                                                    ), a, b),
                                                                                      [v - 1, series[v], 0],
                                                                                      Range(1, Length(_x) / 2 +
                                                                                               1),
                                                                                    )[3], v),
                                                                       Range(
                                                                              1,
                                                                              Length(_x) /
                                                                              2 +
                                                                              1,
                                                                            ),
                                                                     ),
                                                                ),
                                Apply(
                                       (h: list<integer>) => Apply(
                                                                    (ups: list<integer>) => Join(Map(
                                                                                                      Function(h[ups[Length(_x) / 2 +
                                                                                                                     1 -
                                                                                                                     t]] +
                                                                                                               1, t),
                                                                                                      Range(1, Length(_x) / 2),
                                                                                                    ), [1]),
                                                                    Filter(
                                                                            Range(1, Length(_x)),
                                                                            Function(_x[i] == 1, i),
                                                                          ),
                                                                  ),
                                       Map(
                                            Function(Sum(Map(
                                                              Function(
                                                                        2 *
                                                                        _x[k] - 1,
                                                                        k,
                                                                      ),
                                                              Range(1, i),
                                                            )), i),
                                            Range(1, Length(_x)),
                                          ),
                                     ),
                              )

Examples

Basic #

the step word $UUDDUD$

live ↗

In$\mathrm{ProjectivesOfInjectiveDimensionAtMostDominantDimension}({\operatorname{DyckPath}}([1, 1, 0, 0, 1, 0]))$Out$4$

the step word $UDUUDD$

live ↗

In$\mathrm{ProjectivesOfInjectiveDimensionAtMostDominantDimension}({\operatorname{DyckPath}}([1, 0, 1, 1, 0, 0]))$Out$4$

Properties #

FindStat's value for [1,0]

live ↗

In$\mathrm{CombinatorialStat}({\operatorname{DyckPath}}([1, 0]), \text{ProjectivesOfInjectiveDimensionAtMostDominantDimension})$Out$2$

Known value · FindStat St000998

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

live ↗

In$\mathrm{CombinatorialStat}({\operatorname{DyckPath}}([1, 0, 1, 0]), \text{ProjectivesOfInjectiveDimensionAtMostDominantDimension})$Out$3$

Known value · FindStat St000998

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

live ↗

In$\mathrm{CombinatorialStat}({\operatorname{DyckPath}}([1, 1, 0, 0]), \text{ProjectivesOfInjectiveDimensionAtMostDominantDimension})$Out$3$

Known value · FindStat St000998

About

Examples	5
Crosswalk	FindStat