Abstract
A graph has exactly two main eigenvalues if and only if it is a 2-walk linear graph. In this paper, we show some necessary conditions that a 2-walk (a, b)-linear graph must obey. Using these conditions and some basic theorems in graph theory, we characterize all 2-walk linear graphs with small cyclic graphs without pendants. The results are given in sort on unicyclic, bicyclic, tricyclic graphs.
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Foundation item: Supported by the National Natural Science Foundation of China (10671081)
Biography: FAN Qiong, female, Ph. D. c ndidate, Lecturer of Huazhong Normal University, research direction: graph theory.
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Fan, Q., Qi, H. 2-Walk linear graphs with small number of cycles. Wuhan Univ. J. Nat. Sci. 15, 375–379 (2010). https://doi.org/10.1007/s11859-010-0669-8
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DOI: https://doi.org/10.1007/s11859-010-0669-8