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Topic: Another AC anomaly?
Replies: 43   Last Post: Dec 21, 2009 8:08 AM

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Dik T. Winter

Posts: 7,899
Registered: 12/6/04
Re: Another AC anomaly?
Posted: Dec 18, 2009 7:22 AM
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In article <SqSdnSUF1q8FobbWnZ2dnUVZ_uCdnZ2d@giganews.com> "K_h" <KHolmes@SX729.com> writes:
...
> With the second option we
> can restrict ourselves just to the wikipedia definitions and
> define the sets n by:
>
> n = 0 = {}
> n = 1 = {{}}
> n = 2 = {{{}}}
> ...
>
> Wikipedia gives liminf(n-->oo) n = 0.


Only when we use the definition of limit on sequences of sets, not when we
use the definition of limit on sequences of numbers. You have to distinguish
the two and clearly state which one you are using.

> So the notion of n
> growing bigger, as one tends to the limit, is not embodied
> here since |n| is 0,1,1,1,1... as one proceeds and is 0 in
> the limiting case.


Yes, as in many cases: lim | S_n | is not necessarily equal to |lim S_n|,
whatever the definition of set limit. The same holds for limsup and
liminf.
--
dik t. winter, cwi, science park 123, 1098 xg amsterdam, nederland, +31205924131
home: bovenover 215, 1025 jn amsterdam, nederland; http://www.cwi.nl/~dik/



Date Subject Author
12/12/09
Read Re: Another AC anomaly?
Jesse F. Hughes
12/13/09
Read Re: Another AC anomaly?
K_h
12/14/09
Read Re: Another AC anomaly?
Dik T. Winter
12/14/09
Read Re: Another AC anomaly?
K_h
12/15/09
Read Re: Another AC anomaly?
Dik T. Winter
12/15/09
Read Re: Another AC anomaly?
K_h
12/16/09
Read Re: Another AC anomaly?
Dik T. Winter
12/16/09
Read Re: Another AC anomaly?
K_h
12/17/09
Read Re: Another AC anomaly?
Dik T. Winter
12/18/09
Read Re: Another AC anomaly?
K_h
12/18/09
Read Re: Another AC anomaly?
Dik T. Winter
12/18/09
Read Re: Another AC anomaly?
K_h
12/21/09
Read Re: Another AC anomaly?
Dik T. Winter
12/14/09
Read Re: Another AC anomaly?
Dik T. Winter
12/14/09
Read Re: Another AC anomaly?
K_h
12/15/09
Read Re: Another AC anomaly?
Dik T. Winter
12/15/09
Read Re: Another AC anomaly?
Dik T. Winter
12/15/09
Read Re: Another AC anomaly?
K_h
12/16/09
Read Re: Another AC anomaly?
Dik T. Winter
12/17/09
Read Re: Another AC anomaly?
K_h
12/17/09
Read Re: Another AC anomaly?
Dik T. Winter
12/18/09
Read Re: Another AC anomaly?
K_h
12/18/09
Read Re: Another AC anomaly?
K_h
12/18/09
Read Re: Another AC anomaly?
Dik T. Winter
12/18/09
Read Re: Another AC anomaly?
K_h
12/18/09
Read Re: Another AC anomaly?
Dik T. Winter
12/18/09
Read Re: Another AC anomaly?
K_h
12/15/09
Read Re: Another AC anomaly?
K_h
12/16/09
Read Re: Another AC anomaly?
Jesse F. Hughes
12/17/09
Read Re: Another AC anomaly?
Dik T. Winter
12/17/09
Read Re: Another AC anomaly?
Jesse F. Hughes
12/16/09
Read Re: Another AC anomaly?
Dik T. Winter
12/15/09
Read Re: Another AC anomaly?
ross.finlayson@gmail.com
12/13/09
Read Re: Another AC anomaly?
K_h
12/13/09
Read Re: Another AC anomaly?
Jesse F. Hughes
12/13/09
Read Re: Another AC anomaly?
Jesse F. Hughes
12/14/09
Read Re: Another AC anomaly?
Ilmari Karonen
12/14/09
Read Re: Another AC anomaly?
Jesse F. Hughes
12/15/09
Read Re: Another AC anomaly?
Chas Brown

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