关于法国风车的优美性

The Gracefulness of French Windmills

设Ｂ（４，１，ｍ）是具有一个公共点的ｍ个Ｋ４组成的图。Ｊ．Ｃ．Ｂｅｒｍｏｎｄ猜想当ｍ≥４时Ｂ（４，１，ｍ）是优美图，本文证明了当４≤ｍ≤１３时该猜想是成立的。

Let B(n,r,m)be the graph consisting of m copies of K,with a K,in common, where K,is coniplete graph. Bermond has conjectured that B(n,1.m)is graceful for all m≥4.This paper proved the conjecture when 4≤m≤13.