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Topic: Nhood Space
Replies: 24   Last Post: Jul 3, 2013 10:43 PM

 Messages: [ Previous | Next ]
 fom Posts: 1,968 Registered: 12/4/12
Re: Nhood Space
Posted: Jun 30, 2013 10:18 PM

On 6/30/2013 9:45 AM, dullrich@sprynet.com wrote:
> On Sat, 29 Jun 2013 21:39:59 -0700, William Elliot <marsh@panix.com>
> wrote:
>

>> (S,<<) is a nhood space when << is a binary relation for P(S) and
>> for all A,B,C subset S
>> empty set << A << S
>> A << B implies A subset B
>> A << B implies S\B << S\A
>> A << B/\C iff A << B and A << C

>
> You need to clarify the context! We've been through
> this before. Tell us whether
>
> (i) this is an actual definition you saw somewhere
>

These are proximity neighborhoods.

http://en.wikipedia.org/wiki/Proximity_space

Date Subject Author
6/30/13 William Elliot
6/30/13 David C. Ullrich
6/30/13 William Elliot
7/1/13 David C. Ullrich
7/1/13 David C. Ullrich
7/1/13 fom
7/2/13 William Elliot
7/2/13 Peter Percival
7/2/13 William Elliot
7/2/13 fom
7/3/13 fom
7/3/13 William Elliot
7/3/13 William Elliot
6/30/13 fom
6/30/13 Peter Percival
6/30/13 fom
7/1/13 Peter Percival
7/1/13 William Elliot
7/1/13 Peter Percival
7/1/13 William Elliot
7/1/13 Peter Percival
7/1/13 Peter Percival
7/2/13 William Elliot
7/2/13 Peter Percival
7/2/13 William Elliot