Skip to content

ForgottenIndex ​

The sum of the cubes of the degrees.

✓ checked against that system · ! checked, with disagreements (hover a chip)FindStatSt000571via LabeledGraph✓
ForgottenIndex(graph)The sum of the cubes of the degrees.
Typed signatures
TypePackageApplies
(labeled_graph) -> numbercombinatoricsalways

Domain: Graph statistics

Details
  • Defined over LabeledGraph as an expression in _x, evaluated by compute-engine — the definition IS the implementation.
  • Takes a LabeledGraph 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 St000571, the F-index. The graph with no vertices gives 0.

Definition

Epsil, as the implementation runs it.

on LabeledGraph, over _x

0 if _x[1] == 0 else Apply((n: integer) => Apply((edges: list<list<integer>>) => Apply(
                                                                                        (degrees: list<integer>) => Max(Sum(Map(Function(d *
                                                                                                                                         d * d, d), degrees)), 0),
                                                                                        Map(
                                                                                             Function(Max(Sum(Map(Function((1 if e[1] == v else 0) +
                                                                                                                           (1 if e[2] == v else 0), e), edges)), 0), v),
                                                                                             Range(1, n),
                                                                                           ),
                                                                                      ), _x[2]), _x[1])

Examples

Basic #

the graph on 4 vertices with the edges 12, 23, 24 and 34

live ↗
InForgottenIndex(LabeledGraph⁡((4,[[1,2],[2,3],[2,4],[3,4]])))\mathrm{ForgottenIndex}(\operatorname{LabeledGraph}((4,\bigl\lbrack\bigl\lbrack1, 2\bigr\rbrack, \bigl\lbrack2, 3\bigr\rbrack, \bigl\lbrack2, 4\bigr\rbrack, \bigl\lbrack3, 4\bigr\rbrack\bigr\rbrack)))Out4444
Properties #

FindStat's value for ([],1)

live ↗
InCombinatorialStat(LabeledGraph⁡((1,[])),ForgottenIndex)\mathrm{CombinatorialStat}(\operatorname{LabeledGraph}((1,\bigl\lbrack\bigr\rbrack)), \text{ForgottenIndex})Out00

Known value · FindStat St000571

FindStat's value for ([],2)

live ↗
InCombinatorialStat(LabeledGraph⁡((2,[])),ForgottenIndex)\mathrm{CombinatorialStat}(\operatorname{LabeledGraph}((2,\bigl\lbrack\bigr\rbrack)), \text{ForgottenIndex})Out00

Known value · FindStat St000571

FindStat's value for ([],3)

live ↗
InCombinatorialStat(LabeledGraph⁡((3,[])),ForgottenIndex)\mathrm{CombinatorialStat}(\operatorname{LabeledGraph}((3,\bigl\lbrack\bigr\rbrack)), \text{ForgottenIndex})Out00

Known value · FindStat St000571

About
Examples4
CrosswalkFindStat