JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE) ›› 2019, Vol. 54 ›› Issue (6): 2-7.doi: 10.6040/j.issn.1671-9352.0.2019.172

   

The concatenation of thin languages and r-disjunctive languages ——several studies on combinatorial semigroups(Ⅰ)

LIU Zu-hua1,2, GUO Yu-qi1*   

  1. 1. School of Mathematics and Statistics, Lanzhou University, Lanzhou 730000, Gansu, China;
    2. School of Mathematics, Kunming University, Kunming 650214, Yunan, China
  • Published:2019-06-05

Abstract: The background of this paper is from [1] and another paper(1) by Guo et al., we merge some results in above two papers as Proposition 1: L1L∈Df(Dt, Dr)implies L∈Df(Dt, Dr), where L1,L are languages over alphabet A and L1 is finite. In this paper, a new and simple proof of Proposition 1 is given for Dr. It is proved that Proposition 1 is also true for D and Di. Replacing “finite” with “thin”, Proposition 1 is true for D, Df and Dt; and some examples are given which show that Proposition 1 is not true for Di and Dr.

Key words: syntactic congruence, thin language, regular(disjunctive)language, r-regular(disjunctive)language

CLC Number: 

  • O157.4
[1] ZHANG D, GUO Y Q, SHUM K P. On some decompositions of r-disjunctive languages[J]. Bulletin of the Malaysian Mathematical Sciences Society, 2014, 37(3):727-746.
[2] GUO Y Q, REIS C M, THIERRIN G. Relatively f-disjunctive languages[J]. Semigroup Forum, 1988, 37:289-299.
[3] LIU Y, SHUM K P, GUO Y Q. Relatively regular languages and thin codes[J]. European Journal of Combinatorics, 2008, 29:261-267.
[4] GUO Y Q, SHYR H J, THIERRIN G. F-disjunctive languages[J]. International Journal of Computer Mathematics, 1986, 18:219-237.
[5] ITO M. Dense and disjunctive properties of languages[C] // Fundamentals of Computation Theory, International Symposium, Fct '93. Szeged: Springer, 1993: 31-49.
[6] REIS C M. A note on F-disjunctive languages[J]. Semigroup Forum, 1987, 36:159-165.
[7] REIS C M. F-disjunctive congruences and a generalization of monoids with length[J]. Semigroup Forum, 1990, 41:291-306.
[8] SHYR H J, THIERRIN G. Disjunctive Languages and codes, fundamentals of computation theory[C] // Proceeding of the 1977 Inter FCT-Conference, Lecture Notes in Computer Science, No 56. Poznan: Springer-Verlag, 1977: 171-176.
[9] ZHANG D, GUO Y Q, SHUM K P. Some results in r-disjunctive languages and related topics[J]. Soft Computing, 2017, 21(10):2477-2483.
[10] HOWIE J M. Automata and languages[M]. Oxford: Clarendon Press, 1991.
[11] BERSTEL J, PERRIN D. Theory of codes[M]. Orlando: Academic Press, 1985.
[1] SONG Xian-mei, XIONG Lei. MacWilliams identity and self-dual codes of linear codes over Z2a+uZ2a [J]. JOURNAL OF SHANDONG UNIVERSITY(NATURAL SCIENCE), 2016, 51(2): 72-78.
[2] LIU Xiu-sheng, LIU Hua-lu. MacWilliams identities of the linear codes over ring Fp+vFp [J]. J4, 2013, 48(12): 61-65.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
No Suggested Reading articles found!