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تسجيل مستخدم جديدThe unicyclic graphs with the second smallest normalized Laplacian eigenvalue no less than $1-frac{sqrt{6}}{3}$
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Let $lambda_{2}(G)$ be the second smallest normalized Laplacian eigenvalue of a graph $G$. In this paper, we determine all unicyclic graphs of order $ngeq21$ with $lambda_{2}(G)geq 1-frac{sqrt{6}}{3}$. Moreover, the unicyclic graphs with $lambda_{2}(G)=1-frac{sqrt{6}}{3}$ are also determined.
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