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WM used his keyboard to write :The usual term for how an interval could be anythingOn 19.10.2024 20:22, Alan Mackenzie wrote:>WM <wolfgang.mueckenheim@tha.de> wrote:>An infinite set is one which has a proper subset which can be>
put into 1-1 correspondence with the original set. That is the
definition.
According to Dedekind every set {1, 2, 3, ..., n} is in correspondence
with the set {2, 4, 6, ..., 2n} which covers twice the interval,
containing numbers not in the original set. This does not change when
the whole set ℕ is multiplied by 2. The result covers twice the
interval, containing numbers not in the original set ℕ.
Intervals now? Discrete ones or real ones?
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