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Unavoidable regularities and factor permutations of words

Published online by Cambridge University Press:  14 November 2011

W. L. Fouché
Affiliation:
Department of Mathematics and Applied Mathematics, University of Pretoria, 0002 Pretoria, South Africa

Extract

We show that for every finite set A and for every natural number n, there exists a natural number N such that every word of length N over the alphabet A has, for every permutation π of the numbers 1,…,n, a representation of the form Xw1wnzwπ(1)wπ(n) Y, where X, Y are words and w1,…,wn, z are nonempty words over A.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1995

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References

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