Infinite free set for small measure set mappings
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- by Ludomir Newelski, Janusz Pawlikowski and Witold Seredyński PDF
- Proc. Amer. Math. Soc. 100 (1987), 335-339 Request permission
Abstract:
A set $A \subset X$ is free for a function $F:X \to \mathcal {P}(X)$ provided $x \notin F(y)$ for any distinct $x,y \in A$. We show that, if $F$ maps the reals into closed subsets of measure less than 1, then there is an infinite free set for $F$. This solves Problem 38(B) of Erdös and Hajnal [EH].References
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Additional Information
- © Copyright 1987 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 100 (1987), 335-339
- MSC: Primary 04A05; Secondary 04A20, 28A25
- DOI: https://doi.org/10.1090/S0002-9939-1987-0884475-3
- MathSciNet review: 884475