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math1um / objects-invariants-properties

Objects, Invariants and Properties for Graph Theory (GT) automated conjecturing: in particular with the Sage program CONJECTURING: http://nvcleemp.github.io/conjecturing/
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Add invariant: eigenvalue_gap #645

Open math1um opened 3 years ago

math1um commented 3 years ago

let $\lambda_1$ be the largest eigenvalue and $\lambda_2$ be the next largest.

For a graph G let the eigenvalue_gap(G) be $\lambda_1(G)-\lambda_2(G)$.

Question: is this already in gt.sage?

Reference: In Appendix A of Lovasz's Graphs and Geometry.

Doctests: ?