Common Independence in Graphs
نویسندگان
چکیده
The cardinality of a largest independent set G, denoted by α(G), is called the independence number G. domination i(G) graph G smallest dominating We introduce concept common αc(G), as greatest integer r such that every vertex belongs to some subset X VG with |X|≥r. αc(G) limit symmetry in respect fact each an and there are vertices do not belong any larger For relations between above parameters given chain inequalities i(G)≤αc(G)≤α(G). In this paper, we characterize trees T for which i(T)=αc(T), block graphs αc(G)=α(G).
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ژورنال
عنوان ژورنال: Symmetry
سال: 2021
ISSN: ['0865-4824', '2226-1877']
DOI: https://doi.org/10.3390/sym13081411