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 Bandwidth invariant #618

Open math1um opened 3 years ago

math1um commented 3 years ago

from: Dutton, Ronald D., and Robert C. Brigham. "On the size of graphs of a given bandwidth." Discrete mathematics 76, no. 3 (1989): 191-195.

The definition is: (1) a numbering is a bijection f of the vertices with 1...n (where n is the order), (2) an edge value for edge uv with respect to f is |f(u)-f(v)| (3) Bf is the maximum of the edge values with respect to f (4) the bandwidth of the graph is the minimum of Bf for all bijections f.

So this is obviously exponential - but appears in bounds in the cited (and attached) paper. brigham-dutton-size-of-graphs-of-given-bandwidth-1989.pdf