A note on uniquely H-colourable graphs
Anthony Bonato
Discussiones Mathematicae Graph Theory, Tome 27 (2007), p. 39-44 / Harvested from The Polish Digital Mathematics Library
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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.

Publié le : 2007-01-01
EUDML-ID : urn:eudml:doc:270404 
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Anthony Bonato. A note on uniquely H-colourable graphs. Discussiones Mathematicae Graph Theory, Tome 27 (2007) pp. 39-44. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1342/

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