1、1两种四角系统的 Wiener 数和 Hyper-Wiener 数(英文)AbstractIn this paper we deduce the formula of Wiener number and Hyper-Wiener number of two types of polyomino systems. Key wordsWiener number； Hyper-Wiener number； Polyomino systems CLC numberO 157.6Document codeA 1Introduction The topological index W， conceived
2、 by Wiener1more than half a century ago， is one of the most thoroughly studied in chemical graph. Let G be a graph， Wiener number W（G） is defined as follows： Let u and v be two vertices of G， the distance between u and v is equal to the length of a shortest path that connects u and v in the graph G，
3、 which is denoted by d（u，v）. The Wiener number is equal to the sum of the distances between all pairs of vertices of G， In this section， we Calculate the Wiener number and Hyper-Wiener number of two types of polyomino systems. （1）Thefirst type of polyomino system is shown in Figure 1. It is a polyom
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