arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2102.02862math.COcs.DM
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完全超图的边染色到正则染色的推广

Extending Edge-colorings of Complete Hypergraphs into Regular Colorings

Amin Bahmanian

摘要:

令$\binom{X}{h}$为$n$ -集合$X\supseteq Y$的所有$h$ -子集的集合.给定一个集合$S\subseteq \binom{X}{h}$的着色(划分),我们感兴趣的是找到条件,在该条件下,该着色可扩展为$\binom{X}{h}$的着色,使得$X$的每个元素在每个颜色类(所有相同颜色的集合)中出现的次数与$r$相同。$S=\varnothing, r=1$的案例由西尔维斯特在18世纪进行研究,直到20世纪70年代仍然开放。案例$h=2,r=1$在文献中被广泛研究,并且与完成部分对称拉丁方密切相关。对于$S=\binom{Y}{h}$,我们完全解决了$h=4, |X|\geq 4.847323|Y|$和$h=5, |X|\geq 6.285214|Y|$的情况。此外,我们对解决$S=\binom{X}{h}\backslash \binom{Y}{h}$ .这些结果可以被看作是著名的Baranyai定理的推广,并朝着解决Cameron提出的一个40年前的问题取得了进展。

英文摘要:

Let $\binom{X}{h}$ be the collection of all $h$-subsets of an $n$-set $X\supseteq Y$. Given a coloring (partition) of a set $S\subseteq \binom{X}{h}$, we are interested in finding conditions under which this coloring is extendible to a coloring of $\binom{X}{h}$ so that the number of times each element of $X$ appears in each color class (all sets of the same color) is the same number $r$. The case $S=\varnothing, r=1$ was studied by Sylvester in the 18th century, and remained open until the 1970s. The case $h=2,r=1$ is extensively studied in the literature and is closely related to completing partial symmetric Latin squares. For $S=\binom{Y}{h}$, we settle the cases $h=4, |X|\geq 4.847323|Y|$, and $h=5, |X|\geq 6.285214|Y|$ completely. Moreover, we make partial progress toward solving the case where $S=\binom{X}{h}\backslash \binom{Y}{h}$. These results can be seen as extensions of the famous Baranyai's theorem, and make progress toward settling a 40-year-old problem posed by Cameron.

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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