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Penny graph

In geometric graph theory, a penny graph is a contact graph of unit circles. It is formed from a collection of unit circles that do not cross each other, by creating a vertex for each circle and an edge for every pair of tangent circles. The circles can be represented physically by pennies, arranged without overlapping on a flat surface, with a vertex…

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Overview

Properties

Computational complexity

Related graph families

Advanced semantic analysis

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Map overview Semantic statistics

Penny graph

Nodes41
Edges40
Triples42
Avg. degree1.95
Density0.04878
Components1

How this topic connects Entity context

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Penny graph

Top relations

related to Independent sets · 13
Penny graph → As, Baker's, By, Finding, However, In, It, NP-hard, Pach, Paul Erdős, Swanepoel, That, Tóth
related to Coloring · 7
Penny graph → Analogously, Based, Every, For, Grötzsch's, However, Therefore
related to Computational complexity · 7
Penny graph → An, Constructing, Delaunay, However, It, NP-hard, Similarly
related to Number of edges · 7
Penny graph → By, Counting, Every, However, Proving, Some, Swanepoel
is a · 3
Penny graph → contact graph of unit circles, subset of the pennies, unit disk graph and a matchstick graph
related to Related graph families · 3
Penny graph → Because, Penny, The

Important terminology Word statistics

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Important terminology

penny graph graphs circles vertex every unit edges pennies np-hard represented two planar number independent one vertices neighbors however circle

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Penny graphis acontact graph of unit circles0.90text
Penny graphis aunit disk graph and a matchstick graph0.90text
Penny graphis asubset of the pennies0.90text
testing adjacencyinstance ofgiven an input representing its circles in a form allowing basic computational tasks0.80text
finding intersections of the circles with axis-parallel linesinstance ofgiven an input representing its circles in a form allowing basic computational tasks0.80text
Penny graphrelated to ColoringEvery0.60section
Penny graphrelated to ColoringFor0.60section
Penny graphrelated to ColoringTherefore0.60section
Penny graphrelated to ColoringBased0.60section
Penny graphrelated to ColoringHowever0.60section
Penny graphrelated to ColoringAnalogously0.60section
Penny graphrelated to ColoringGrötzsch's0.60section

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    Min side: 3
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