On factorization forests of finite height
نویسندگان
چکیده
Simon (Theoret. Comput. Sci. 72 (1990) 65–94) has proved that every morphism from a free semigroup to a $nite semigroup S admits a Ramseyan factorization forest of height at most 9|S|. In this paper, we prove the same result of Simon with an improved bound of 7|S|. We provide a simple algorithm for constructing a factorization forest. In addition, we show that the algorithm cannot be improved signi$cantly. We give examples of semigroup morphism such that any Ramseyan factorization forest for the morphism would require a height not less than |S|. c © 2003 Elsevier B.V. All rights reserved.
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عنوان ژورنال:
- Theor. Comput. Sci.
دوره 310 شماره
صفحات -
تاریخ انتشار 2004