Wikipedia:Reference desk/Archives/Mathematics/2012 July 10

Mathematics desk
< July 9 << Jun | July | Aug >> July 11 >
Welcome to the Wikipedia Mathematics Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.


July 10

edit

Pythagorean triples

edit

In Pythagorean triples, it says "Every integer greater than 2 is part of a primitive or non-primitive Pythagorean triple, for example, the integers 6, 10, 14, and 18 are not part of primitive triples, but are part of the non-primitive triples 6, 8, 10; 14, 48, 50 and 18, 80, 82". How does one go about proving that?

I can get as far as proving that the "first integer not in the above set must be a prime". But then I get stuck. -- 84.12.125.33 (talk) 11:16, 10 July 2012 (UTC)[reply]

Let a be any odd number above 1. Choose m = n+1 in the first formula in Pythagorean triple#Generating a triple, and then choose n so a = m2 - n2. PrimeHunter (talk) 11:36, 10 July 2012 (UTC)[reply]