On spaces extremal for the Gomory-Hu inequality

O. Dovgoshey, E. Petrov, H. -M. Teichert

Let $(X,d)$ be a finite ultrametric space. In 1961 E.C. Gomory and T.C. Hu proved the inequality $|Sp(X)|⩽|X|$ where $Sp(X)=\{d(x,y):x,y\in X\}$. Using weighted Ham…