The size of the set of left invariant means on an ELA semigroup

Author:
Alan L. T. Paterson

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

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Abstract: Let *S* be an ELA semigroup and let be the smallest possible cardinality of the set as *F* ranges over the finite subsets of *S*. The main purpose of this note is to show that if is infinite, then *S* has exactly (multiplicative) left invariant means.

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DOI:
https://doi.org/10.1090/S0002-9939-1978-0493156-4

Article copyright:
© Copyright 1978
American Mathematical Society