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Jun 20, 2022 at 10:55 answer added Bennett McElwee timeline score: 3
Apr 13, 2017 at 12:58 history edited CommunityBot
replaced http://mathoverflow.net/ with https://mathoverflow.net/
Dec 28, 2013 at 23:32 vote accept user44653
Dec 27, 2013 at 10:56 comment added Asaf Karagila Ya know... this is the fourth question on this sort of puzzle over MO and MSE, and I still can't figure out what any of these have to do with the axiom of choice. I mean, sure, it's needed, but the axiom is also needed in constructing maximal ideals, ultrafilters, etc.
Dec 27, 2013 at 4:10 answer added Eric Naslund timeline score: 16
Dec 26, 2013 at 23:30 history edited user44653 CC BY-SA 3.0
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Dec 26, 2013 at 23:18 comment added user44653 Good points about the countable sets of functions and thanks for the uncountability observation. In point of fact, the notion of the boxes being in "sequence" is unnecessary. A better way to describe the puzzle is probably to say there is a set of boxes cardinality $\alpha$, and to ask for the maximum cardinality $\beta$ of a set of strategies guaranteed to make at most $\gamma$ wrong guesses. But of course the countable/countable case is the most natural.
Dec 26, 2013 at 9:12 comment added Victor This is an outcry of mathematical thought: "can an infinite number of mathematicians..."
Dec 25, 2013 at 23:18 comment added Dan Turetsky I have a negative answer to the uncountable question. Notice that the behavior of a strategy doesn't depend on the value of the box it guesses at. If you're faced with uncountably many mathematicians, begin by placing 0 in all the boxes. By pigeon hole, there's some box that uncountably many of the mathematicians guess at. Adjust the value at that box to make most of them wrong.
Dec 25, 2013 at 21:56 comment added Noah Schweber Just a quick observation: your argument about the case when $f$ is guaranteed to be computable isn't really about computability theory: a much stronger fact is true, namely if we are guaranteed that $f$ is in some pre-determined countable set of functions $\mathbb{N}\rightarrow\mathbb{R}$, then $k$ can be $\omega$.
Dec 25, 2013 at 12:09 history edited user44653 CC BY-SA 3.0
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Dec 25, 2013 at 8:49 review First posts
Dec 25, 2013 at 10:32
Dec 25, 2013 at 8:32 history asked user44653 CC BY-SA 3.0