A characterization of the graphs with high degree sum that are not covered by three cycles
نویسندگان
چکیده
Let G be a graph of order n. In [10], Saito characterized the graphs with σ3(G) ≥ n− 1 that are not covered by two cycles. In this paper, we characterize the graphs with σ4(G) ≥ n − 1 that are not covered by three cycles. Moreover, to prove our main theorem, we show several new results which are useful in the study of this area.
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ورودعنوان ژورنال:
- Ars Comb.
دوره 128 شماره
صفحات -
تاریخ انتشار 2016