Dergiler / Turkish Journal of Mathematics / 2019 / Cilt: 43 - Sayı: 1

A broken cycle theorem for the restrained chromatic function

Sayfa
355–360
Yayın Tarihi
2022-11-04
DOI
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⚡ TL;DR(1 Cümlede Hızlı Çıkarım)

We provide an extension of this result by finding combinatorial interpretationsof the coefficients of the restrained chromatic function

📌 3 Maddede Bu Makale

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Amaç & Hipotez:A restraint r on a graph G is a function that assigns each vertex of the graph a finite subset of N.
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Temel Bulgular & Veri:Whitney’s celebratedbroken cycle theorem gives a combinatorial interpretation of the coefficients of the chromatic polynomial via certainsubgraphs (the so-called broken cycles).
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Sonuç & Katkı:We provide an extension of this result by finding combinatorial interpretationsof the coefficients of the restrained chromatic function
🔬Tür:Araştırma Makalesi
📍Kapsam:Genişletilmiş Akademik Örneklem
⚙️Değişkenler:Alan Parametreleri

Abstract

A restraint r on a graph G is a function that assigns each vertex of the graph a finite subset of N. For eachvertex v of the graph, r(v) is called the set of colors forbidden at v . A proper coloring of G is said to be permittedby a given restraint r if each vertex v of the graph receives a color that is not from its set of forbidden colors r(v) .The restrained chromatic function, denoted by r(G; x) , is a function whose evaluations at integer x values count thenumber of proper x-colorings of the graph G permitted by the restraint r and this function is known to be a polynomialfunction of x for large enough x. The restrained chromatic function r(G; x) is a generalization of the well-knownchromatic polynomial (G; x) , as r(G; x) = (G; x) if r(v) = ∅ for each vertex v of the graph. Whitney’s celebratedbroken cycle theorem gives a combinatorial interpretation of the coefficients of the chromatic polynomial via certainsubgraphs (the so-called broken cycles). We provide an extension of this result by finding combinatorial interpretationsof the coefficients of the restrained chromatic function

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Bu Makaleye Atıf Yap

EREY, A. (2022). A broken cycle theorem for the restrained chromatic function. Turkish Journal of Mathematics, Cilt: 43 - Sayı: 1, 355–360. https://ajindex.com/articles/607691

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Kaynakça (21)

  1. Alon N. Restricted colorings of graphs. In: Proceedings of the 14th British Combinatorial Conference; Cambridge; 1993. pp. 1-33
  2. Björner A, Ziegler G. Broken circuit complexes: factorizations and generalizations. J Combin Theory Ser B 1991; 51: 96-126
  3. Blass A, Sagan BE. Möbius functions of lattices. Adv Math 1997; 127: 94-123
  4. Brown JI, Erey A. Restraints permitting the largest number of colourings. Discrete Appl Math 2017; 222: 76-88
  5. Brown JI, Erey A, Li J. Extremal restraints for graph colourings. J Comb Math Comb Comput 2015; 93: 297-304
  6. Brylawski T. The broken-circuit complex. T Am Math Soc 1977; 234: 417-433
  7. Brylawski T, Oxley J. Several identities for the characteristic polynomial of a combinatorial geometry. Discrete Math 1980; 31: 161-170
  8. Dohmen K, Pönitz A, Tittmann P. A new two-variable generalization of the chromatic polynomial. Discrete Math Theor Comput Sci 2003; 6: 69-89
  9. Dohmen K, Trinks M. An abstraction of Whitney’s broken circuit theorem. Electron J Combin 2014; 21: 4.32
  10. Donner Q. On the number of list-colorings. J Graph Theory 1992; 16: 239-245
  11. Erey A. An investigation on graph polynomials. PhD, Dalhousie University, Halifax, Canada, 2015
  12. Huh J. h-Vectors of matroids and logarithmic concavity. Adv Math 2015; 270: 49-59
  13. Kubale M. Interval vertex-colouring of a graph with forbidden colours. Discrete Math 1989; 74: 125-136
  14. Llamas A, Martínez-Bernal J, Merino C. On the broken-circuit complex of graphs. Comm Algebra 2010; 38: 1847- 1854
  15. Nakamura M. On the NBC-complexes and -invariants of abstract convex geometries. Discrete Appl Math 2009; 157: 1799-1805
  16. Thomassen C. The chromatic polynomial and list colorings. J Combin Theory Ser B 2009; 99: 474-479
  17. Toft B. Color-critical graphs and hypergraphs. J Combin Theory Ser B 1974; 16: 145-161
  18. Trinks M. A note on a broken-cycle theorem for hypergraphs. Discuss Math Graph Theory 2014; 34: 641-646
  19. Tuza Z. Graph colorings with local restrictions - A survey. Discuss Math Graph Theory 1997; 17: 161-228
  20. Wang W, Qian J, Yan Z. When does the list-coloring function of a graph equal its chromatic polynomial. J Combin Theory Ser B 2017, 122: 543-549
  21. Whitney H. A logical expansion in mathematics. B Am Math Soc 1932; 38: 572-579.