Maximal Digraphs with Respect to Primitive Positive Constructability
نویسندگان
چکیده
We study the class of all finite directed graphs up to primitive positive constructability. The resulting order has a unique greatest element, namely graph $P_1$ with one vertex and no edges. lower bound, $P_2$ two vertices edge. Our main result is complete description bounds $P_2$; we call these submaximal. show that every not equivalent below submaximal graphs.
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ژورنال
عنوان ژورنال: Combinatorica
سال: 2022
ISSN: ['0209-9683', '1439-6912']
DOI: https://doi.org/10.1007/s00493-022-4918-1