In this paper we define the property of homomorphic compactness for digraphs. We prove that if a digraph H is homomorphically compact then H has a core, although the converse does not hold. We also examine a weakened compactness condition and show that when this condition is assumed, compactness is
Core-like properties of infinite graphs and structures
โ Scribed by B. Bauslaugh
- Publisher
- Elsevier Science
- Year
- 1995
- Tongue
- English
- Weight
- 554 KB
- Volume
- 138
- Category
- Article
- ISSN
- 0012-365X
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โฆ Synopsis
We define several properties of infinite graphs (structures) which are analogous to the property of being a core in a finite graph. We describe completely the relationships between these properties. We also show which of these properties are invariant under homomorphic equivalence.
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