禁用子图 meaning in English

forbidding subgraph

These questions are special cases of the so called forbidden subgraph problem .
这些问题都是所谓禁用子图问题的特殊情形。
But usually it is difficult to work out the hamilton problem of any graph , then we turn to explore the graphs containing forbidden subgraph , for example , claw - free graph , almost claw - free graph , quasi claw - free graph
由于直接研究任一图类的hamilton问题往往比较困难，于是人们转而研究含有某些禁用子图的图类，如：无爪图，几乎无爪图，拟无爪图等