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arXiv · 1905.11134

Graph quasivarieties

Erkko Lehtonen·Reinhard Pöschel
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Abstract

Introduced by C. R. Shallon in 1979, graph algebras establish a useful connection between graph theory and universal algebra. This makes it possible to investigate graph varieties and graph quasivarieties, i.e., classes of graphs described by identities or quasi-identities. In this paper, graph quasivarieties are characterized as classes of graphs closed under directed unions of isomorphic copies of finite strong pointed subproducts.

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Erkko Lehtonen, Reinhard Pöschel. 2019-05-27. Graph quasivarieties. https://doi.org/10.14232/actasm-019-528-9

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