Simultaneous idempotents in 𝛽𝐍_{𝐍} and finite sums and products in 𝐍

Hindman, Neil

doi:10.1090/S0002-9939-1979-0539649-3

Simultaneous idempotents in $\beta \mathbf{N}_{\mathbf{N}}$ and finite sums and products in

Author: Neil Hindman
Journal: Proc. Amer. Math. Soc. 77 (1979), 150-154
MSC: Primary 05A17; Secondary 10A45, 54D40
DOI: https://doi.org/10.1090/S0002-9939-1979-0539649-3
MathSciNet review: 539649
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Abstract: The principal result is that there do not exist simultaneous multiplicative and additive idempotents in $\beta N\backslash N$ . Some consequences of the (already known) existence of multiplicative idempotents which are close to additive idempotents are also derived.

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