The size of the set of left invariant means on an ELA semigroup
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- by Alan L. T. Paterson PDF
- Proc. Amer. Math. Soc. 72 (1978), 62-64 Request permission
Abstract:
Let S be an ELA semigroup and let $\mathfrak {m}(S)$ be the smallest possible cardinality of the set $\{ s \in S:Fs = \{ s\} \}$ as F ranges over the finite subsets of S. The main purpose of this note is to show that if $\mathfrak {m}(S)$ is infinite, then S has exactly ${2^{{2^{\mathfrak {m}(S)}}}}$ (multiplicative) left invariant means.References
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Additional Information
- © Copyright 1978 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 72 (1978), 62-64
- MSC: Primary 43A07
- DOI: https://doi.org/10.1090/S0002-9939-1978-0493156-4
- MathSciNet review: 0493156