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Topic: Why not Hausdorff's ordered pairs
Replies: 70   Last Post: Feb 25, 2012 3:01 AM

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 namducnguyen Posts: 2,334 Registered: 12/13/04
Re: Why not Hausdorff's ordered pairs
Posted: Feb 21, 2012 9:36 PM

On 21/02/2012 7:30 PM, Nam Nguyen wrote:
> On 21/02/2012 7:16 PM, Shmuel (Seymour J.) Metz wrote:
>> at 06:44 PM, Nam Nguyen<namducnguyen@shaw.ca> said:
>>

>>> Fwiw, I found the definition (a,b)={{a},{a,b}} a little "annoyed" in
>>> that (a,a) is reduced to a singleton set.

>>
>> That fact doesn't bother me; it still seems like the simplest
>> definition.
>>

>>> (I've not spent time to see if (a,a,a) is also the same!)
>>
>>
>> That would deped on how you defined it.

>
> I meant by using the same definition above [(a,b)={{a},{a,b}}].
>
> If my calculation isn't wrong, (a,a,a) is:

[where (a,b,c) <-> ((a,b),c).]

> {
> {{{a},{a}}},
> {{{a},{a}},a}
> }
>
> which is not a singleton as (a,a). So that's why I found
> it a bit "annoying": they'd don't seem to be "consistent".
>
> Not that I'm protesting anything. I agree it shouldn't matter
> much at all which definition is used.

--
----------------------------------------------------
There is no remainder in the mathematics of infinity.

NYOGEN SENZAKI
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Date Subject Author
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2/20/12 Kaba
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2/21/12 Chris Menzel
2/21/12 Shmuel (Seymour J.) Metz
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2/21/12 namducnguyen
2/21/12 Shmuel (Seymour J.) Metz
2/21/12 namducnguyen
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2/22/12 Shmuel (Seymour J.) Metz
2/22/12 namducnguyen
2/22/12 Shmuel (Seymour J.) Metz
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2/22/12 Herman Rubin
2/22/12 Zaljohar@gmail.com
2/22/12 Graham Cooper
2/22/12 Graham Cooper
2/22/12 Graham Cooper
2/22/12 Chris Menzel
2/22/12 Graham Cooper
2/23/12 Graham Cooper
2/23/12 Herman Rubin
2/23/12 Graham Cooper
2/23/12 Zaljohar@gmail.com
2/23/12 Zaljohar@gmail.com
2/23/12 Zaljohar@gmail.com
2/23/12 Graham Cooper
2/23/12 Zaljohar@gmail.com
2/23/12 Zaljohar@gmail.com
2/23/12 Zaljohar@gmail.com
2/23/12 Herman Rubin
2/23/12 Graham Cooper
2/23/12 Zaljohar@gmail.com
2/23/12 Graham Cooper
2/23/12 Zaljohar@gmail.com
2/23/12 Graham Cooper
2/23/12 Graham Cooper
2/24/12 Zaljohar@gmail.com
2/24/12 Graham Cooper
2/24/12 Zaljohar@gmail.com
2/24/12 Zaljohar@gmail.com
2/24/12 Graham Cooper
2/24/12 Zaljohar@gmail.com
2/24/12 Zaljohar@gmail.com
2/24/12 Zaljohar@gmail.com
2/24/12 Graham Cooper
2/24/12 Zaljohar@gmail.com
2/24/12 Graham Cooper
2/24/12 Zaljohar@gmail.com
2/24/12 Graham Cooper
2/24/12 Graham Cooper
2/24/12 Zaljohar@gmail.com
2/24/12 Graham Cooper
2/25/12 Zaljohar@gmail.com
2/25/12 Graham Cooper
2/23/12 Zaljohar@gmail.com
2/23/12 Graham Cooper
2/23/12 Zaljohar@gmail.com
2/23/12 Zaljohar@gmail.com
2/23/12 Graham Cooper
2/23/12 Zaljohar@gmail.com
2/23/12 Graham Cooper
2/23/12 Zaljohar@gmail.com
2/23/12 Shmuel (Seymour J.) Metz
2/21/12 Zaljohar@gmail.com
2/22/12 Zaljohar@gmail.com
2/22/12 Graham Cooper