论文标题
可数的塞施图的兄弟姐妹
Siblings of countable cographs
论文作者
论文摘要
我们表明，每个可数的Cograph都有一个或无限的兄弟姐妹。这很部分地回答了Thomassé的猜想。主要工具是准订购良好的概念以及Cographs和一些标记的有序树之间的对应关系。
We show that every countable cograph has either one or infinitely many siblings. This answers, very partially, a conjecture of Thomassé. The main tools are the notion of well quasi ordering and the correspondence between cographs and some labelled ordered trees.
