Re: Existence of function

On 1 Sep 2005 18:37:28 -0700, agapito6314@xxxxxxx wrote:

>Actually what I meant to ask is: How does one prove that there is a
>surjection from NxN to S (which is a countable union of countable
>sets)? Can you get by here without invoking AC? Thanks.

If you've asked exactly the question you meant to ask the answer
is no, that's exactly the step that requires AC.


************************

David C. Ullrich
.

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