Extremal Graphs in Connectivityaugmentationtibor
نویسندگان
چکیده
Let A(n; k; t) denote the smallest integer e for which every k-connected graph on n vertices can be made (k + t)-connected by adding e new edges. We determine A(n; k; t) for all values of n; k and t in the case of (directed and undirected) edge-connectivity and also for directed vertex-connectivity. For undirected vertex-connectivity we determine A(n; k; 1) for all values of n and k. We also describe the graphs which attain the extremal values.
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