A note on uniquely H-colorable graphs
نویسنده
چکیده
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.
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عنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 27 شماره
صفحات -
تاریخ انتشار 2007