👉 In mathematics, a double-ganger is a property of a graph that indicates whether two vertices are connected by an edge. The term was first used in 1962 by the mathematician John H. Conway and his student Robert P. Schmuck for the case where the graph has only one vertex. A double-ganger means that there exists a path between any two vertices in the graph. For example, consider the following undirected graph: ``` 0 /
