Abstract.
Let E be an equivalence relation on the powerset of an uncountable set, which is reasonably definable. We assume that any two subsets with symmetric difference of size exactly 1 are not equivalent. We investigate whether for E there are many pairwise non equivalent sets.
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I would like to thank Alice Leonhardt for the beautiful typing.
This research was supported by The Israel Science Foundation. Publication 724.
Mathematics Subject Classification (2000): 03E47, 03E35; 20K20, 20K35
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Shelah, S. On nice equivalence relations on λ2. Arch. Math. Logic 43, 31–64 (2004). https://doi.org/10.1007/s00153-003-0183-1
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DOI: https://doi.org/10.1007/s00153-003-0183-1