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# Calling all positive integers ...

Started by bonanova, May 06 2013 05:20 AM

5 replies to this topic

### #1

Posted 06 May 2013 - 05:20 AM

OK maybe not all.

How many pairs of mutually prime positive integers sum to 2x10

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.

How many pairs of mutually prime positive integers sum to 2x10

^{250}?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.

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

- Bertrand Russell

### #2

Posted 06 May 2013 - 09:07 AM Best Answer

Spoiler for

### #3

Posted 06 May 2013 - 08:54 PM

Spoiler for I get

### #4

Posted 06 May 2013 - 09:42 PM

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

### #5

Posted 07 May 2013 - 03:26 AM

Spoiler for I get

Spoiler for consider

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

- Bertrand Russell

### #6

Posted 07 May 2013 - 02:55 PM

Spoiler for I get

Spoiler for considerIt seems rather difficult to pull the wool over the Denizens!

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