arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2108.02685math.CO
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不正则子图

Irregular Subgraphs

Noga Alon, Fan Wei

摘要:

本文提出了两个相关的定理来处理图的生成不规则子图的存在性。第一个断言,任何$d$ -正则图上的$n$顶点包含一个生成子图,其中$0$和$d$之间的每个度的顶点数偏离$\frac{n}{d+1}$最多$2$。第二个条件是$n$顶点上的每一个最小度$δ$的图都包含一个生成子图,其中每个度的顶点数不超过$\frac{n}{δ+1}+2$。这两个结构仍然开放,但我们证明了几个渐近松弛的图与大量的顶点$n$。特别地,我们证明了,如果$d^3 \log n \leq o(n)$,那么每个$d$ -正则图与$n$顶点包含一个生成子图,其中$0$和$d$之间的每个度的顶点数是$(1+o(1))\frac{n}{d+1}$。我们还证明了任何具有$n$顶点和最小度$δ$的图都包含一个生成子图,其中没有度重复超过$(1+o(1))\frac{n}{δ+1}+2$次。

英文摘要:

We suggest two related conjectures dealing with the existence of spanning irregular subgraphs of graphs. The first asserts that any $d$-regular graph on $n$ vertices contains a spanning subgraph in which the number of vertices of each degree between $0$ and $d$ deviates from $\frac{n}{d+1}$ by at most $2$. The second is that every graph on $n$ vertices with minimum degree $δ$ contains a spanning subgraph in which the number of vertices of each degree does not exceed $\frac{n}{δ+1}+2$. Both conjectures remain open, but we prove several asymptotic relaxations for graphs with a large number of vertices $n$. In particular we show that if $d^3 \log n \leq o(n)$ then every $d$-regular graph with $n$ vertices contains a spanning subgraph in which the number of vertices of each degree between $0$ and $d$ is $(1+o(1))\frac{n}{d+1}$. We also prove that any graph with $n$ vertices and minimum degree $δ$ contains a spanning subgraph in which no degree is repeated more than $(1+o(1))\frac{n}{δ+1}+2$ times.

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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