A note on uniquely H-colourable graphs

Anthony Bonato

Discussiones Mathematicae Graph Theory (2007)

  • Volume: 27, Issue: 1, page 39-44
  • ISSN: 2083-5892

Abstract

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For a graph H, we compare two notions of uniquely H-colourable graphs, where one is defined via automorphisms, the second by vertex partitions. We prove that the two notions of uniquely H-colourable are not identical for all H, and we give a condition for when they are identical. The condition is related to the first homomorphism theorem from algebra.

How to cite

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Anthony Bonato. "A note on uniquely H-colourable graphs." Discussiones Mathematicae Graph Theory 27.1 (2007): 39-44. <http://eudml.org/doc/270404>.

@article{AnthonyBonato2007,
abstract = {For a graph H, we compare two notions of uniquely H-colourable graphs, where one is defined via automorphisms, the second by vertex partitions. We prove that the two notions of uniquely H-colourable are not identical for all H, and we give a condition for when they are identical. The condition is related to the first homomorphism theorem from algebra.},
author = {Anthony Bonato},
journal = {Discussiones Mathematicae Graph Theory},
keywords = {graph homomorphisms; core graphs; uniquely H-colourable},
language = {eng},
number = {1},
pages = {39-44},
title = {A note on uniquely H-colourable graphs},
url = {http://eudml.org/doc/270404},
volume = {27},
year = {2007},
}

TY - JOUR
AU - Anthony Bonato
TI - A note on uniquely H-colourable graphs
JO - Discussiones Mathematicae Graph Theory
PY - 2007
VL - 27
IS - 1
SP - 39
EP - 44
AB - For a graph H, we compare two notions of uniquely H-colourable graphs, where one is defined via automorphisms, the second by vertex partitions. We prove that the two notions of uniquely H-colourable are not identical for all H, and we give a condition for when they are identical. The condition is related to the first homomorphism theorem from algebra.
LA - eng
KW - graph homomorphisms; core graphs; uniquely H-colourable
UR - http://eudml.org/doc/270404
ER -

References

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