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Example

The set R is not countable.

Every infinite sequence d of decimal digits represents a real number

0.d0d1d2....

Since the set of all infinite sequences is not countable (and every real number is represented by a countable set of such sequences), also R is not countable.

Not all number domains are countable.


Author: Wolfgang Schreiner
Last Modification: December 7, 1999

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