Abstract
We present necessary conditions for the diagonal bi-act \(_S(S\times S)_S\) over an epigroup \(S\) to be finitely generated. They imply that this bi-act is not finitely generated whenever \(S\) is infinite and locally finite. This solves a problem posed by Gallagher.
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The second author was supported in part by the NSF Grant DMS 1161294.
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Communicated by Mikhail Volkov.
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Kozhukhov, I.B., Olshanskii, A.Y. Diagonal bi-acts over semigroups with finiteness conditions. Semigroup Forum 91, 538–542 (2015). https://doi.org/10.1007/s00233-014-9661-5
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DOI: https://doi.org/10.1007/s00233-014-9661-5