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On vertex k-partitions of certain infinite graphs

✍ Scribed by Douglas Cenzer; Edward Howorka


Publisher
Elsevier Science
Year
1978
Tongue
English
Weight
826 KB
Volume
23
Category
Article
ISSN
0012-365X

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✦ Synopsis


Let G be an infinite graph; define de& G to be the least m such that any partition P of the vertex set of G into sets of uniformly bounded cardinality contains a set which is adjacent to at least m Other sets of the partition. If G is either a regular tree 01 a triangtiisr, sqzart or hexagonal planar mosaic graph, it is shown that deg, G equals the degree of G. This verifies some conjectures of S. Ulam. Several open problems are given.


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