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From: Lawrence D'Oliveiro <ldo@nz.invalid>
Newsgroups: comp.theory
Subject: Re: Cantor Diagonal Proof
Date: Fri, 4 Apr 2025 02:29:55 -0000 (UTC)
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On Fri, 4 Apr 2025 02:41:09 +0100, Mike Terry wrote:

> On 03/04/2025 23:18, Lawrence D'Oliveiro wrote:
>
>> The Cantor diagonal construction is an algorithm for computing an
>> incomputable number.
> 
> It is not an algorithm for computing something.  Algorithms are
> instructions that operate on finite inputs and must terminate with an
> answer at some point for every input.

The definition of a “computable number” is that for any integer N, there 
is an algorithm that will compute digit N of the number in a finite 
sequence of steps.

Does the Cantor diagonal construction fit this definition? Yes it does.