${\delta }_k$-small sets in graphs

Asen Bojilov, Nedyalko Nenov

Let $G$ be a simple $n$-vertex graph and $W\subseteq\V(G)$. We say that $W$ is a ${\delta }_k$-small set if $$ \sqrt[k]{\frac{\sum_{v\in W}d^k(v)}{\abs W}}\leq n-\abs W. $$ Let $φ^{(k)}(G)…