Harries graph

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Harries graph
Harries graph.svg
The Harries graph
Named afterW. Harries
Vertices 70
Edges 105
Radius 6
Diameter 6
Girth 10
Automorphisms 120 ( S5 )
Chromatic number 2
Chromatic index 3
Genus 9
Book thickness 3
Queue number 2
Properties Cubic
Cage
Triangle-free
Hamiltonian
Table of graphs and parameters

In the mathematical field of graph theory, the Harries graph or Harries (3-10)-cage is a 3-regular, undirected graph with 70 vertices and 105 edges. [1]

Contents

The Harries graph has chromatic number 2, chromatic index 3, radius 6, diameter 6, girth 10 and is Hamiltonian. It is also a 3-vertex-connected and 3-edge-connected, non-planar, cubic graph. It has book thickness 3 and queue number 2. [2]

The characteristic polynomial of the Harries graph is

History

In 1972, A. T. Balaban published a (3-10)-cage graph, a cubic graph that has as few vertices as possible for girth 10. [3] It was the first (3-10)-cage discovered but it was not unique. [4]

The complete list of (3-10)-cage and the proof of minimality was given by O'Keefe and Wong in 1980. [5] There exist three distinct (3-10)-cage graphs—the Balaban 10-cage, the Harries graph and the Harries–Wong graph. [6] Moreover, the Harries–Wong graph and Harries graph are cospectral graphs.

Related Research Articles

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<span class="mw-page-title-main">Harries–Wong graph</span>

In the mathematical field of graph theory, the Harries–Wong graph is a 3-regular undirected graph with 70 vertices and 105 edges.

<span class="mw-page-title-main">Balaban 10-cage</span> Cubic graph with 70 nodes and 105 edges

In the mathematical field of graph theory, the Balaban 10-cage or Balaban (3,10)-cage is a 3-regular graph with 70 vertices and 105 edges named after Alexandru T. Balaban. Published in 1972, It was the first 10-cage discovered but it is not unique.

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<span class="mw-page-title-main">Balaban 11-cage</span> 3-regular graph

In the mathematical field of graph theory, the Balaban 11-cage or Balaban (3,11)-cage is a 3-regular graph with 112 vertices and 168 edges named after Alexandru T. Balaban.

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<span class="mw-page-title-main">Dyck graph</span>

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<span class="mw-page-title-main">Nauru graph</span> 24-vertex symmetric bipartite cubic graph

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<span class="mw-page-title-main">Tutte 12-cage</span>

In the mathematical field of graph theory, the Tutte 12-cage or Benson graph is a 3-regular graph with 126 vertices and 189 edges. It is named after W. T. Tutte.

<span class="mw-page-title-main">Klein graphs</span>

In the mathematical field of graph theory, the Klein graphs are two different but related regular graphs, each with 84 edges. Each can be embedded in the orientable surface of genus 3, in which they form dual graphs.

<span class="mw-page-title-main">110-vertex Iofinova–Ivanov graph</span> Semi-symmetric cubic graph with 110 vertices and 165 edges

The 110-vertex Iofinova–Ivanov graph is, in graph theory, a semi-symmetric cubic graph with 110 vertices and 165 edges.

References

  1. Weisstein, Eric W. "Harries Graph". MathWorld .
  2. Jessica Wolz, Engineering Linear Layouts with SAT. Master Thesis, University of Tübingen, 2018
  3. A. T. Balaban, A trivalent graph of girth ten, J. Combin. Theory Ser. B 12, 1-5. 1972.
  4. Pisanski, T.; Boben, M.; Marušič, D.; and Orbanić, A. "The Generalized Balaban Configurations." Preprint. 2001. .
  5. M. O'Keefe and P.K. Wong, A smallest graph of girth 10 and valency 3, J. Combin. Theory Ser. B 29 (1980) 91-105.
  6. Bondy, J. A. and Murty, U. S. R. Graph Theory with Applications. New York: North Holland, p. 237, 1976.