优美图是图论中重要的研究课题之一,有着广泛的应用价值和研究前景。但是目前仍然很难从理论上对一般图的优美性进行研究。马克杰猜想:所有优美图的冠都是优美图。这一猜想至今没有被证明或否定。对任何正整数m和n,用构造的方法给出了图I(1-Fm,4)和I(K1,1,1,n)的优美标号,从而证明了I(1-Fm,4)和I(K1,1,1,n)都是优美图。
Graceful graph is one of the important research topics in graph theory with wide application and research prospects. But now it is still difficult to study the gracefulness of general graphs in theory.Ma Kejie conjecture is that all the coronas of graceful graph are graceful graphs. This conjecture has not been proved or denied. For any positive integers m and n,the constructor method gives graceful labeling of I( 1- Fm,4) and I( K1,1,1,n),thus prove that I( 1- Fm,4) and I( K1,1,1,n) are graceful graphs.