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Totally commutative semigroups

Published online by Cambridge University Press:  09 April 2009

Józef Dudek
Affiliation:
Institute of Mathematics Wroclaw UniversityP1. Grunwaldzki 2/4 50-384 Wroclaw, Poland
Andrzej Kisielewicz
Affiliation:
Institute of Mathematics Technical University of WroclawWybrzeze Wyspianskiego 27 50-370 Wroclaw, Poland
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Abstract

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A semigroup is totally commutative if each of its essentially binary polynomials is commutative, or equivalently, if in every polynomial (word) every two essential variables commute. In the present paper we describe all varieties (equational classes) of totally commutative semigroups, lattices of subvarieties for any variety, and their free spectra.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1991

References

[1]Aczél, I., ‘Proof of a theorem on distributive type hyperidentities’, Algebra Universalis 1 (1971), 16.CrossRefGoogle Scholar
[2]Birjukov, A. P., ‘Varieties of idempotent semigroups’, Algebra i Logika 9 (1970), 255273.Google Scholar
[3]Belousov, V. D., ‘Systems of quasigroups with generalized identities’, Uspekhi Mat. Nauk 20 (1965), 75146.Google Scholar
[4]Bergman, G. M., ‘Hyperidentities of groups and semigroups’, Aequationes Math. 23 (1971), 5065.CrossRefGoogle Scholar
[5]Berman, J., ‘Free spectra of 3-element algebras’, Universal algebra and lattice theory, Proc. Puebla 1982, edited by Freese, R. S. and Garcia, O. O., pp. 1053, Lecture Notes in Math., vol. 1004, Springer-Verlag, Berlin and New York, 1983, pp. 10–53.CrossRefGoogle Scholar
[6]Evans, T., ‘Some connections between residual finiteness, finite embeddability and the word problem’, J. London Math. Soc. (2) 1 (1969), 399403.CrossRefGoogle Scholar
[7]Fennemore, C., ‘All varieties of bands’, Semigroup Forum 1 (1970), 172179.CrossRefGoogle Scholar
[8]Gerhard, J. A., ‘The lattice of equational clases of idempotent semigroups’, J. Algebra 15 (1970), 195224.CrossRefGoogle Scholar
[9]Gerhard, J. A., ‘The number of polynomials of idempotent semigroups’, J. Algebra 18 (1971), 366376.CrossRefGoogle Scholar
[10]Gerhard, J. A., ‘The word problem for semigroups satisfying x 3 = x’, Math. Proc. Cambridge Philos. Soc. 84 (1978), 1119.CrossRefGoogle Scholar
[11]Gerhard, J. A. and Petrich, M., ‘All varieties of regular orthogroups’, Semigroup Forum 31 (1985), 311351.CrossRefGoogle Scholar
[12]Gerhard, J. A. and Petrich, M., ‘Word problem for free objects in certain varieties of completely regular semigroups’, Pacific J. Math. 104 (1983), 351359.CrossRefGoogle Scholar
[13]Grätzer, G., Composition of functions, Proc. Conf. on Universal Algebra, pp. 1106 (Queen's University, Kingston, Ont., 1969).Google Scholar
[14]Grätzer, G. and Padmanabhan, R., ‘On idempotent, commutative and nonassociative groupoids’, Proc. Amer. Math. Soc. 28 (1971), 7580.CrossRefGoogle Scholar
[15]Hall, T. E. and Jones, P. R., ‘On the lattice of varieties of bands of groups’, Pacific J. Math. 91 (1980), 327337.CrossRefGoogle Scholar
[16]Kisielewicz, A., ‘Characterization of pn-sequences for non-idempotent algebras’, J. Algebra 108 (1987), 102115.CrossRefGoogle Scholar
[17]Petrich, M., Lectures in semigroups, (Wiley, London, 1977).CrossRefGoogle Scholar
[18]Taylor, W., ‘Hyperidentities and hypervarieties’, Aequationes Math. 23 (1981), 3049.CrossRefGoogle Scholar
[19]Taylor, W., ‘Equational logic’, Houston J. Math. (1979).Google Scholar