Просмотр кода страницы Removal of a set of vertices

'''Removal of a set of vertices''' --- удаление множества вершин. 

For a given graph (digraph or hypergraph) <math>G</math>, removal of vertices in
<math>X</math> together with all edges incident to them. The resulting [hyper-,
di-]graph is denoted by <math>G \setminus X</math> or <math>G - X</math>. If <math>X = \{x\}</math>, it is simply <math>G - x</math>.