arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1905.03388math.CO
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关于循环图的整数{k}-控制数

On the integer {k}-domination number of circulant graphs

Yen-Jen Cheng, Hung-Lin Fu, Chia-an Liu

摘要:

设$G=(V,E)$是一个简单的无向图。$G$是定义在$V=\mathbb{Z}_n$上的循环图,其差集为$D\subseteq \{1,2,\ldots,\lfloor\frac{n}{2}\rfloor\}$,条件是$\mathbb{Z}_n$中的两个顶点$i$和$j$相邻当且仅当$\min\{|i-j|, n-|i-j|\}\in D$ .为了方便起见,我们使用$G(n;D)$来表示这样的循环图。函数$f:V(G)\rightarrow\mathbb{N}\cup\{0\}$是整数$\{k\}$ -控制函数,如果对于每个$v\in V(G)$,$\sum_{u\in N_G[v]}f(u)\geq k.$通过考虑所有$\{k\}$ -控制函数$f$,$\sum_{v\in V(G)}f(v)$的最小值是$G$的$\{k\}$ -控制数,用$γ_k(G)$表示.本文证明了如果$D=\{1,2,\ldots,t\}$,$1\leq t\leq \frac{n-1}{2}$,则$G(n;D)$的整数$\{k\}$ -控制数是$\lceil\frac{kn}{2t+1}\rceil$ .

英文摘要:

Let $G=(V,E)$ be a simple undirected graph. $G$ is a circulant graph defined on $V=\mathbb{Z}_n$ with difference set $D\subseteq \{1,2,\ldots,\lfloor\frac{n}{2}\rfloor\}$ provided two vertices $i$ and $j$ in $\mathbb{Z}_n$ are adjacent if and only if $\min\{|i-j|, n-|i-j|\}\in D$. For convenience, we use $G(n;D)$ to denote such a circulant graph. A function $f:V(G)\rightarrow\mathbb{N}\cup\{0\}$ is an integer $\{k\}$-domination function if for each $v\in V(G)$, $\sum_{u\in N_G[v]}f(u)\geq k.$ By considering all $\{k\}$-domination functions $f$, the minimum value of $\sum_{v\in V(G)}f(v)$ is the $\{k\}$-domination number of $G$, denoted by $γ_k(G)$. In this paper, we prove that if $D=\{1,2,\ldots,t\}$, $1\leq t\leq \frac{n-1}{2}$, then the integer $\{k\}$-domination number of $G(n;D)$ is $\lceil\frac{kn}{2t+1}\rceil$.

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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