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Re: Matheology § 152
Posted:
Nov 17, 2012 1:13 PM
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On 17 Nov., 18:57, Uirgil <uir...@uirgil.ur> wrote:
> > > > Consider the following sequence of decimal numbers, consisting of > > > > digits 0 and 1 > > > > > 01. > > > > 0.1 > > > > 010.1 > > > > 01.01 > > > > 0101.01 > > > > 010.101 > > > > 01010.101 > > > > 0101.0101 > > > > ... > > > > > which, when indexed by natural numbers, yilooks like this: > > > > > 0_2 1_1 . > > > > 0_2 . 1_1 > > > > 0_4 1_3 0_2 . 1_1 > > > > 0_4 1_3 . 0_2 1_1 > > > > 0_6 1_5 0_4 1_3 . 0_2 1_1 > > > > 0_6 1_5 0_4 . 1_3 0_2 1_1 > > > > 0_8 1_7 0_6 1_5 0_4 . 1_3 0_2 1_1 > > > > 0_8 1_7 0_6 1_5 . 0_4 1_3 0_2 1_1 > > > > ...
> While every real mathematician knows
This sequence grows without limit. > > > This can be proved by taking any number n and showing > > that there is a number k such that all for terms a(j) of the sequence > > with k > j we have a(j) > n. Proof: For given n take k = n + 10. > > ow does that work for the sequence a(j) = 0 for all j?
Is 0 larger than any number n?
> > > Every set theorist knows that the sequence of sets of indices left of > > the decimal point has the limit empty set. This is an requirement of > > set theory. > > Then let us see which axiom, or set of axioms, of some set theory which > actually requires such nonsense. say among the axioms for ZFC, for > example.
Try to learn it. Look what William Hughes just explains here. > > > > > And finally everybody knows that decimal numbers, by definition, > > cannot consist of digits that have no indexs. > > Numbers (decimal or otherwise) can exist without any digits of any sort, > but decimal numerals can not.
But the numbers in above list exist with their digits. > > Since a numeral is merely a name for a number,
the set of all numbers is countable.
Regards, WM
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