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On Indecomposable Graphs

Published online by Cambridge University Press:  20 November 2018

Frank Harary
Affiliation:
The University of Michigan
Michael D. Plummer
Affiliation:
The University of Michigan
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A set of points M of a graph G is a point cover if each line of G is incident with at least one point of M. A minimum cover (abbreviated m.c.) for G is a point cover with a minimum number of points. The point covering number α(G) is the number of points in any minimum cover of G. Let [V1, V2, … , Vr], r > 1 be a partition of V(G), the set of points of G. Let Gi be the subgraph of G spanned by Vi for i = 1, 2, … , r.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1967

References

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