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arXiv 1808.09650math.CO
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树与二分度序列的匹配数

The matching number of tree and bipartite degree sequences

F. Bock, D. Rautenbach

摘要:

本文研究了具有给定度序列的所有树以及具有给定二部度序列的所有二部图的匹配数的可能值。对于树的度序列,我们得到了可能值的闭公式。对于二分度序列,我们展示了具有限制结构的实现的存在性,这使得可以导出一个类似的Gale-Ryser定理表征二分度序列。更精确地说,我们证明了一个二分度序列有一个实现与一定的匹配数当且仅当一个立方数的不等式类似的Gale-Ryser定理满足。对于树度序列和二部度序列,匹配数的可能值形成区间。

英文摘要:

We study the possible values of the matching number among all trees with a given degree sequence as well as all bipartite graphs with a given bipartite degree sequence. For tree degree sequences, we obtain closed formulas for the possible values. For bipartite degree sequences, we show the existence of realizations with a restricted structure, which allows to derive an analogue of the Gale-Ryser Theorem characterizing bipartite degree sequences. More precisely, we show that a bipartite degree sequence has a realization with a certain matching number if and only if a cubic number of inequalities similar to those in the Gale-Ryser Theorem are satisfied. For tree degree sequences as well as for bipartite degree sequences, the possible values of the matching number form intervals.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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