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Chris M. Thomasson submitted this idea :Agreed. Think of something like:On 9/21/2024 4:25 PM, Richard Damon wrote:You could think of them as a sequence of ordered pairs of naturals.On 9/21/24 9:57 AM, WM wrote:>On 21.09.2024 01:06, Richard Damon wrote:>On 9/20/24 2:33 PM, WM wrote:>>How can 10 points exist in linear order without a first one?Who says they can't.>
In order to count to 10, you have to start at 1.>>
Its just when they become infinite that there might be ends that don't exist.
In order to count a countable set, you have to start at 1.
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Regards, WM
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Right, so the countable numbers have ONE end that can be used to count from.
What about the signed integers? Well, we can always start from origin, at 0. ;^)
((0,0),(1,0),(1,1),(2,0),(2,1),...)
First of the pair is the magnitude and the second of the pair is the sign where one equals negation. The sequence is one-ended and perhaps now more obviously countable.
(0,1,-1,2,-2,3,-3,...)
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