Homomorphism-Homogeneous Relational Structures
نویسندگان
چکیده
We study relational structures (especially graphs and posets) which satisfy the analogue of homogeneity but for homomorphisms rather than isomorphisms. The picture is rather different. Our main results are partial characterisations of countable graphs and posets with this property; an analogue of Fraı̈ssé’s Theorem; and representations of monoids as endomorphism monoids of such structures. ∗This research was carried out while the first author was visiting KAM/ITI in Prague. He is grateful to the Department and Institute for their hospitality. †Supported by a Czech grant LN00A056 and ICREA, Barcelona.
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ورودعنوان ژورنال:
- Combinatorics, Probability & Computing
دوره 15 شماره
صفحات -
تاریخ انتشار 2006