M-chain graphs of posets
نویسندگان
چکیده
Covering graphs of various types of finite partially ordered sets have been extensively studied since Ore in [2] asked for a characterization of such graphs in general. In this note we introduce a graph, called the m-chain graph of a poset, that reduces to the covering graph when m = 1. Since we will show how to construct the m-chain graph for m > 2 as the 2-chain graph of another poset, we are concerned primarily with 2-chain graphs. Utilizing the line diagraph of the oriented covering graph of a poset, we characterize the 2-chain graphs of posets whose covering graphs are trees.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 74 شماره
صفحات -
تاریخ انتشار 1989