Universality vs Genericity and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="d1e184" altimg="si3.svg"><mml:msub><mml:mrow><mml:mi>C</mml:mi></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub></mml:math>-free graphs
نویسندگان
چکیده
We show that the existence of a universal structure implies generic for any approximable class C countable structures. also converse is not true. As consequence, we provide several new examples weak Fraïssé classes finite graphs. Finally, all C4-free graphs does contain structure, strengthening result A. Hajnal and J. Pach.
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2022
ISSN: ['1095-9971', '0195-6698']
DOI: https://doi.org/10.1016/j.ejc.2022.103590