- #1

cragar

- 2,552

- 3

## Homework Statement

Prove that 2n is representable when n is. Is the converse true?

Representable is when a positive integer can be written

as the sum of 2 integral squares.

## The Attempt at a Solution

so n can be written as [itex] x^2+y^2 [/itex]

x and y are positive integers

so then [itex] 2n=2(x^2+y^2) [/itex]

I am not really sure where to go next, maybe i should look a the prime factors.

Just to make sure that i know what converse is,

Would the converse be if 2n is representable so is n.