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A result on B 1 -groups

Ladislav Bican, K. M. Rangaswamy (1995)

Rendiconti del Seminario Matematico della Università di Padova

A scoop from groups: equational foundations for loops

Phillips, J. D., Petr Vojtěchovský (2008)

Commentationes Mathematicae Universitatis Carolinae

Groups are usually axiomatized as algebras with an associative binary operation, a two-sided neutral element, and with two-sided inverses. We show in this note that the same simplicity of axioms can be achieved for some of the most important varieties of loops. In particular, we investigate loops of Bol-Moufang type in the underlying variety of magmas with two-sided inverses, and obtain ``group-like'' equational bases for Moufang, Bol and C-loops. We also discuss the case when the inverses are only...

A semilattice of varieties of completely regular semigroups

Mario Petrich (2020)

Mathematica Bohemica

Completely regular semigroups are unions of their (maximal) subgroups with the unary operation within their maximal subgroups. As such they form a variety whose lattice of subvarieties is denoted by ( 𝒞 ) . We construct a 60-element -subsemilattice and a 38-element sublattice of ( 𝒞 ) . The bulk of the paper consists in establishing the necessary joins for which it uses Polák’s theorem.

A short direct characterization of GS-quasigroups

Zdenka Kolar-Begović (2011)

Czechoslovak Mathematical Journal

The theorem about the characterization of a GS-quasigroup by means of a commutative group in which there is an automorphism which satisfies certain conditions, is proved directly.

A short proof of a theorem of Brodskii.

James Howie (2000)

Publicacions Matemàtiques

A short proof, using graphs and groupoids, is given of Brodskii’s theorem that torsion-free one-relator groups are locally indicable.

A short proof of Eilenberg and Moore’s theorem

Maria Nogin (2007)

Open Mathematics

In this paper we give a short and simple proof the following theorem of S. Eilenberg and J.C. Moore: the only injective object in the category of groups is the trivial group.

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