# Sum is unique?

if u have 3 primes: x,y,z
then prove its sum m=x+y+z is unique ? Thank you

## Answers and Replies

matt grime
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As stated it is a none question: given any three numbers there is a unique number that is their sum.

Oh I stated probme incorectly,
let x,y,z be primes, m=x+y+z
Can u find other three primes that can sum to get m ? m can be any number.

matt grime
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Of course you can. You should try it. It's possible to find infinitely many counter examples, and there is a number less than 20 that is the sum of two primes in two different ways.

Tide
Science Advisor
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matt grime said:
It's possible to find infinitely many counter examples, and there is a number less than 20 that is the sum of two primes in two different ways.

Yes, but the question concerns three primes! shmoe
Science Advisor
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Tide said:
Yes, but the question concerns three primes! So add the same prime to both pairs.

Tide
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shmoe said:
So add the same prime to both pairs.

Of course. Nevermind! Mollet1955 said:
Oh I stated probme incorectly,
let x,y,z be primes, m=x+y+z
Can u find other three primes that can sum to get m ? m can be any number.
I think that by other you have to find three totally different primes.

This too is easy 3+13+31 = 7+11+29. Again, using 3 and 7, and two sets of twin primes. there are infinitely many examples assuming that their are infinitely many pairs of twin primes.

If so, I think I can't go on solvin this problme
Clearly a simple sum repeated day after day, trying to complicate the main porblme :rofl: