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Cancellation in semigroups in which \(x^ 2=x^ 3\). (English) Zbl 0695.20033

The author presents a discussion of the semigroup B(k,m,n), which is the free semigroup generated by k elements and satisfying \(x^ m=x^ n\), where m is a nonnegative integer and n is an integer which is greater than m. Results relating to cancellation in the semigroup which is the union of B(k,2,3) for \(k=1,2,..\). are discussed in detail.
Reviewer: J.A.Hildebrant

MSC:

20M05 Free semigroups, generators and relations, word problems
20M07 Varieties and pseudovarieties of semigroups

References:

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