Skip to main content
Log in

The product of the idempotents and an \(\mathcal{H}\)-class of the finite full transformation semigroup

  • RESEARCH ARTICLE
  • Published:
Semigroup Forum Aims and scope Submit manuscript

Abstract

We investigate the set products S=EH, where E is the set of idempotents of a finite full transformation semigroup T X and H is an arbitrary \(\mathcal{H}\)-class of T X . We show that S is a semigroup and is a union of \(\mathcal{H}\)-classes of T X . We determine the nature of this union through use of Hall’s Marriage Lemma. We describe Green’s relations and thereby show that S has regular elements of all possible ranks and that \(\operatorname{Reg}(S)\) forms a right ideal of S.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Higgins, P.M., Howie, J.M., Ruskuc, N.: Set products in transformation semigroups. Proc. R. Soc. Edinb. 133A, 1121–1136 (2003)

    Article  MathSciNet  Google Scholar 

  2. Higgins, P.M., Howie, J.M., Ruskuc, N.: Generators and factorisations of transformation semigroups. Proc. R. Soc. Edinb. 128A, 1355–1369 (1998)

    Article  MathSciNet  Google Scholar 

  3. Higgins, P.M.: Techniques of Semigroup Theory. Oxford University Press, London (1992)

    MATH  Google Scholar 

  4. Howie, J.M.: Fundamentals of Semigroup Theory. Oxford University Press, London (1995)

    MATH  Google Scholar 

  5. Iwahori, N., Nagao, H.: On the automorphism group of the full transformation semigroups. Proc. Jpn. Acad. 48(9), 639–640 (1972)

    Article  MathSciNet  MATH  Google Scholar 

  6. Mal’cev, A.I.: Symmetric groupoids. Mat. Sb. (N.S.) 31, 136–151 (1952)

    MathSciNet  Google Scholar 

  7. Schreier, I.: Über Abbildungen einer Abstrakten Menge auf Ihre Teilmengen. Fundam. Math. 28, 261–264 (1936)

    MATH  Google Scholar 

  8. Wilson, R.J.: Introduction to Graph Theory, 5th edn. Pearson Education, Upper Saddle River (2010)

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Peter M. Higgins.

Additional information

Communicated by Jean-Eric Pin.

Dedicated to the memory of John Mackintosh Howie (1936–2011).

Rights and permissions

Reprints and permissions

About this article

Cite this article

Higgins, P.M. The product of the idempotents and an \(\mathcal{H}\)-class of the finite full transformation semigroup. Semigroup Forum 84, 203–215 (2012). https://doi.org/10.1007/s00233-012-9373-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00233-012-9373-7

Keywords

Navigation