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A Degree Sum Condition for the Existence of a Contractible Edge in a κ-Connected Graph

✍ Scribed by Matthias Kriesell


Publisher
Elsevier Science
Year
2001
Tongue
English
Weight
184 KB
Volume
82
Category
Article
ISSN
0095-8956

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✦ Synopsis


It is known that a noncomplete }-connected graph of minimum degree of at least w 5} 4 x contains a }-contractible edge, i.e., an edge whose contraction yields again a }-connected graph. Here we prove the stronger statement that a noncomplete }-connected graph for which the sum of the degrees of any two distinct vertices is at least 2 w 5 4 }x&1 possesses a }-contractible edge. The bound is sharp and remains valid and sharp if we look only at degree sums at pairs of vertices at distances of one or two, provided that }{7.


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