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October 1, 2026
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A counterexample on outer inverses in semigroups

Linear Algebra and its Applications. 2017. Vol. 513. P. 120–121.
Shitov Y.

We construct a counterexample to the following conjecture, which was proposed recently by Bapat et al. ‘If a is a regular element in a semigroup S, and x is an outer inverse of a, then a has a reflexive generalized inverse y which dominates x with respect to the minus order on S.’

Priority areas: mathematics
Language: English
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Keywords: semigroupтеория полугрупп
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