在相关文献基础上给出了三个树的等价性命题,并做了简单证明。通过考虑树与单圈图的性质,类似地给出了单圈图的十个等价性命题,并采取简单易证的方式,利用循环套的形式证明了它们的等价性。
Three new propositions are presented about the equivalence of trees on the reference, and their equivalence are proved. In addition, it is given that ten equivalent propositions of unicyclic graph by considering the properties of the graph and tree. It is verified that by simple and new proofs for the ten equivalent definitions.