DP-coloring (also known as correspondence coloring) is a generalization of list coloring introduced recently by Dvořák and Postle [12]. Many known upper bounds for the list-chromatic number extend to the DP-chromatic number, but not all of them do. In this note we describe some properties of DP-coloring that set it aside from list coloring. In particular, we give an example of a planar bipartite graph with DP-chromatic number 4 and prove that the edge-DP-chromatic number of a d-regular graph with d ⩾ 2 is always at least d + 1.

中文翻译：

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DP着色和列表着色之间的差异

DP着色（也称为对应着色）是Dvořák和Postle [12]最近引入的列表着色的概括。列表色数的许多已知上限都扩展到DP色数，但并非所有人都可以。在本说明中，我们描述了DP着色的一些属性，这些属性将其与列表着色分开。特别是，我们得到具有DP-色数4的平面的二部图的例子，并且证明的边缘-DP-色数d -regular图表与d ⩾2总是至少d + 1。