Core (graph theory)

In graph theory, the term "core" refers to a specific type of subgraph that captures some essential structural properties of the original graph. A **core** of a graph is often defined as a maximal subgraph in which every vertex has a degree (number of edges connected to it) of at least \( k \). This means that for a \( k \)-core, every vertex in the graph has at least \( k \) connections.