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arXiv 1712.08780math.CO
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乘积图的Grundy全控制数

On Grundy total domination number in product graphs

Boštjan Brešar, Csilla Bujtás, Tanja Gologranc, Sandi Klavžar, Gašper Košmrlj, Tilen Marc, Balázs Patkós, Zsolt Tuza, Máté Vizer

摘要:

图$G$的顶点的最长序列$(v_1,\ldots,v_k)$是$G$的Grundy全控制序列,如果对所有$i$,有$N(v_i) \setminus \bigcup_{j=1}^{i-1}N(v_j)\not=\emptyset$ .序列的长度$k$称为$G$的Grundy全控制数,记为$γ_{gr}^{t}(G)$。本文研究了四种标准积图的Grundy全控制数。对于直积,我们证明了$γ_{gr}^t(G\times H) \geq γ_{gr}^t(G)γ_{gr}^t(H)$,猜想等式总是成立,并在几种特殊情况下证明了猜想。对于字典序积,我们用因子的相关不变量来表示$γ_{gr}^t(G\circ H)$,并给出了它的一些显式公式,对于强积,我们证明了$γ_{gr}^t(G \boxtimes H)$的下界以及路和圈的积的上界.对于笛卡儿积,我们证明了当因子是路或圈时,Grundy全控制数的上下界。

英文摘要:

A longest sequence $(v_1,\ldots,v_k)$ of vertices of a graph $G$ is a Grundy total dominating sequence of $G$ if for all $i$, $N(v_i) \setminus \bigcup_{j=1}^{i-1}N(v_j)\not=\emptyset$. The length $k$ of the sequence is called the Grundy total domination number of $G$ and denoted $γ_{gr}^{t}(G)$. In this paper, the Grundy total domination number is studied on four standard graph products. For the direct product we show that $γ_{gr}^t(G\times H) \geq γ_{gr}^t(G)γ_{gr}^t(H)$, conjecture that the equality always holds, and prove the conjecture in several special cases. For the lexicographic product we express $γ_{gr}^t(G\circ H)$ in terms of related invariant of the factors and find some explicit formulas for it. For the strong product, lower bounds on $γ_{gr}^t(G \boxtimes H)$ are proved as well as upper bounds for products of paths and cycles. For the Cartesian product we prove lower and upper bounds on the Grundy total domination number when factors are paths or cycles.

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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