It is shown that a plane near triangulated graph is chordal if and only if it does not contain any induced wheel $W_n$ for $n \ge 5$. A necessary and sufficient condition for a $W_5$ free plane near triangulation to be perfect is also derived.
翻译:显示接近三角方位图的平面只有在不包含任何引轮(W_n$n)或5美元/Ge5美元的情况下,才为圆形。 还可以得出一个必要和充分的条件,使靠近三角方位图的免费平面(W_5美元)完美无缺。