RAIRO - Theoretical Informatics and Applications

Research Article

From Bi-ideals to Periodicity

Jānis Bulsa1 and Aivars Lorencsa2

a1 Department of Mathematics, University of Latvia, Raiņa bulvāris 19, Rīga, 1586, Latvia; buls@fmf.lu.lv; web site:

a2 Institute of Electronics and Computer Science, Dzērbenes street 14, Rīga, 1006, Latvia; lorencs@edi.lv


The necessary and sufficient conditions are extracted for periodicity of bi-ideals. They cover infinitely and finitely generated bi-ideals.

(Online publication June 3 2008)

Key Words:

  • Periodic words;
  • bi-ideals;
  • the sequence generates the bi-ideal;
  • finitely generated bi-ideals

Mathematics Subject Classification:

  • 68R15;
  • 94A55;
  • 68Q15