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 binding_number invariant #627

Open math1um opened 3 years ago

math1um commented 3 years ago

binding_number = min(|N(U)|/|U|, over all non-empty subsets U of the vertex set V, where N(U) is not all of V)

N(U) = neighbors of U

as described it is clearly exponential - considering all subsets is exponential.

ADD to intractable_invariants list

defined in:

Woodall, D. R. "The binding number of a graph and its Anderson number." Journal of Combinatorial Theory, Series B 15, no. 3 (1973): 225-255.