A characterization of trees having a minimum vertex cover which is also a minimum total dominating set ∗
نویسندگان
چکیده
∗The authors thank the financial support received from Grant UNAM-PAPIIT IN114415 and SEP-CONACyT. Also, the first author would like to thank the support of the Post-Doctoral Fellowships program of DGAPA-UNAM. †email: [email protected] (Corresponding Author) ‡[email protected] §[email protected] 1 ar X iv :1 70 5. 00 21 6v 1 [ m at h. C O ] 2 9 A pr 2 01 7 A vertex cover of a graph G = (V,E) is a set X ⊆ V such that each edge of G is incident to at least one vertex of X. A dominating set D ⊆ V is a total dominating set of G if the subgraph induced by D has no isolated vertices. A (γt − τ)-set of G is a minimum vertex cover which is also a minimum total dominating set. In this article we give a constructive characterization of trees having a (γt − τ)-set.
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