Near automorphisms of trees with small total relative displacements
نویسندگان
چکیده
For a permutation f of the vertex set V (G) of a connected graph G, let δf (x, y)= |d(x, y)− d(f (x), f (y))|. Define the displacement δf (G) of G with respect to f to be the sum of δf (x, y) over all unordered pairs {x, y} of distinct vertices of G. Let π(G) denote the smallest positive value of δf (G) among the n! permutations f of V (G). In this note, we determine all trees T with π(T )= 2 or 4.
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ورودعنوان ژورنال:
- J. Comb. Optim.
دوره 14 شماره
صفحات -
تاریخ انتشار 2007