论文标题
在公平列表上图形的树木
On Equitable List Arboricity of Graphs
论文作者
论文摘要
张在2016年推出的公平清单营养性,除了在每个颜色类的大小上,除了通常的上限外,还要求每个颜色类引起的acyclic(而不是无毛线),从而概括了公平列表着色的概念。图形$ g $是公平的$ k $清单,如果对于$ g $的每个列表分配的$ g $都有公平的列表颜色,该列表分配的$ g $与每个顶点相关联,$ g $ in $ g $ a List $ k $可用的颜色。张猜想,任何图形$ g $都是满足$ k \ geq \ lceil(1+δ(g))/2 \ rceil $的每种$ k $的$ k $清单。我们通过应用新的引理来验证循环能力的猜想,该引理是扩展部分公平的,可提高的列表颜色的一般工具。我们还为某些连接的图形提出了张的猜想的更强版本:任何连接的图形$ g $都是$ k $ list的$ k $ list,每个$ k $满足$ k \ geq \ geq \lceilδ(g)/2 \ rceil $ g $ n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n n DECE既不是循环的循环图形。我们验证了Zhang的猜想的这种更强大的版本,以实现路径,2级图和某些其他图的幂。我们还表明,如果$ g $是公平的$ k $ list Arborable,则不一定要遵循$ g $是公平的$(k+1)$ - 列表arborable,它解决了Drgas-Burchardt,Furmanczyk和Sidorowicz(2018)的问题。
Equitable list arboricity, introduced by Zhang in 2016, generalizes the notion of equitable list coloring by requiring the subgraph induced by each color class to be acyclic (instead of edgeless) in addition to the usual upper bound on the size of each color class. Graph $G$ is equitably $k$-list arborable if an equitable, arborable list coloring of $G$ exists for every list assignment for $G$ that associates with each vertex in $G$ a list of $k$ available colors. Zhang conjectured that any graph $G$ is equitably $k$-list arborable for each $k$ satisfying $k \geq \lceil (1+Δ(G))/2 \rceil$. We verify this conjecture for powers of cycles by applying a new lemma which is a general tool for extending partial equitable, arborable list colorings. We also propose a stronger version of Zhang's Conjecture for certain connected graphs: any connected graph $G$ is equitably $k$-list arborable for each $k$ satisfying $k \geq \lceil Δ(G)/2 \rceil$ provided $G$ is neither a cycle nor a complete graph of odd order. We verify this stronger version of Zhang's Conjecture for powers of paths, 2-degenerate graphs, and certain other graphs. We also show that if $G$ is equitably $k$-list arborable it does not necessarily follow that $G$ is equitably $(k+1)$-list arborable which addresses a question of Drgas-Burchardt, Furmanczyk, and Sidorowicz (2018).