| In 1972,D.Perrin showed that the monoid of prefix codes is a free monoid,then the irreducible generating set of prefix code is a code.In order to explore the freedom of the monoid related to the prefix code,in 1975,H.J.Shyr found six subsets in monoid of prefix languages that were able to generate free monoids.In 1998,H.J.Shyr and Y.S.Tsai proved that the monoid generated by irreducible finite prefix codes with the set of the powers of primitive words is a free monoid.In this paper,we found it correct when removed the condition of finite in the result of 1998 and we provided a free monoid consisting of all prefix codes,which expanded the research area of free monoid related the prefix code.In 2004,Zheng-Zhu Li and Y.S.Tsai presented a result of codes with three elements in the Fibonacci languages.The paper we study a code with four elements in the Fibonacci languages and we also provide some results of codes with three elements with different structures in the Fibonacci languages. |
PDF Full Text Request