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A characterization of retracts in certain Fraïssé limits

✍ Scribed by Igor Dolinka

Publisher
John Wiley and Sons
Year
2011
Tongue
English
Weight
150 KB
Volume
58
Category
Article
ISSN
0044-3050

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✦ Synopsis

Abstract

Assuming certain conditions on a class \documentclass{article}\usepackage{amssymb,amsmath,mathrsfs}\begin{document}\pagestyle{empty}$\mathscr{C}$\end{document} of finitely generated first‐order structures admitting the model‐theoretical construction of a Fraïssé limit, we characterize retracts of such limits as algebraically closed structures in a class naturally related to \documentclass{article}\usepackage{amssymb,amsmath,mathrsfs}\begin{document}\pagestyle{empty}$\mathscr{C}$\end{document}. In this way we generalize an earlier description of retracts of the countably infinite random graph.

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