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Alternating Whitney sums and matchings in trees, part 1

✍ Scribed by Robert E Jamison


Publisher
Elsevier Science
Year
1987
Tongue
English
Weight
673 KB
Volume
67
Category
Article
ISSN
0012-365X

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✦ Synopsis


The number of k-node subtrees of a tree is its kth Whitney number. This paper investigates the behavior of certain alternating sums of these Whitney numbers and shows how they are related to the structure of maximum matchings in the tree. It is shown that the alternating sum of the Whitney numbers gives the maximum cardinality of an independent set of nodes. Moreover, a weighted alternating sum yields the number of nodes left uncovered by at least one maximum matching.


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