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Functions and line digraphs

โœ Scribed by Amine El Sahili


Book ID
102342540
Publisher
John Wiley and Sons
Year
2003
Tongue
English
Weight
84 KB
Volume
44
Category
Article
ISSN
0364-9024

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โœฆ Synopsis


Abstract

Consider two maps f and g from a set E into a set F such that f(x)โ€‰โ‰ โ€‰g(x) for every x in E. Suppose that there exists a positive integer n such that for any element z in F either f^โˆ’1^(z) or g^โˆ’1^(z) has at most n elements. Then, E can be partitioned into 2__n__โ€‰+โ€‰1 subsets E~1~, E~2~,โ€ฆ,E~2__n__โ€‰+โ€‰1~ such that f(E~i~)โˆฉ g(E~i~)โ€‰=โ€‰ฯ•, 1โ€‰โ‰คโ€‰iโ€‰โ‰คโ€‰2__n__โ€‰+โ€‰1. ยฉ 2003 Wiley Periodicals, Inc. J Graph Theory 44: 296โ€“303, 2003


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