Formal Definition
Formally, an intersection graph is an undirected graph formed from a family of sets
- Si, i = 0, 1, 2, ...
by creating one vertex vi for each set Si, and connecting two vertices vi and vj by an edge whenever the corresponding two sets have a nonempty intersection, that is,
- E(G) = {{vi, vj} | Si ∩ Sj ≠ ∅}.
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