We show that if is a 3-vertex-connected -free graph of order and radius , then the inequality holds. Moreover, graphs are constructed to show that the bounds are asymptotically sharp.

中文翻译：

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3点连通图的半径的上界

我们证明，如果是一个3顶点连接的，自由的阶数和半径图，则不等式持有。此外，构建图以显示边界渐近尖锐。