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Calling all positive integers ...


Best Answer witzar, 06 May 2013 - 09:07 AM

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#1 bonanova

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Posted 06 May 2013 - 05:20 AM

OK maybe not all.
 
How many pairs of mutually prime positive integers sum to 2x10250?
 
You should be able to do this on the back of an envelope, and probably can't count the pairs with a simple program (before the earth freezes.)
 
Pairs differing only in the order of addition count as 1 pair, not as 2 different pairs.
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#2 witzar

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Posted 06 May 2013 - 09:07 AM   Best Answer

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#3 superprismatic

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Posted 06 May 2013 - 08:54 PM

Spoiler for I get


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#4 dark_magician_92

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Posted 06 May 2013 - 09:42 PM

Agree with Superprismatic. I think u have counted (1, 2*10^250-1) also.


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#5 bonanova

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Posted 07 May 2013 - 03:26 AM

Spoiler for I get

 

Spoiler for consider


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#6 superprismatic

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Posted 07 May 2013 - 02:55 PM

 

Spoiler for I get

 

Spoiler for consider

It seems rather difficult to pull the wool over the Denizens!


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