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%I #9 Sep 03 2019 15:11:19
%S 1,1,1,2,5,28,223,3151,79673,3853870
%N Number of connected graphs on n unlabeled nodes with diameter equal to radius.
%C When the graph diameter is equal to the radius, every node has the same eccentricity and is in both the graph center and the graph periphery.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GraphCenter.html">Graph Center</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GraphPeriphery.html">Graph Periphery</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Distance_(graph_theory)">Distance (graph theory)</a>
%Y Rightmost diagonal of A294525 and A324244.
%K nonn,more
%O 1,4
%A _Andrew Howroyd_, Sep 02 2019