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## Discussion of Problem 1356. Something Easier

Hint..
Posted by esger 3 Dec 2012 02:58
Be sure that(at least for the given interval, [4,2*10^9]) every even number can be shown as sum of two prime numbers.

1. if n is prime, {n}
2. if n is even, {n = p1 + p2}
3. if n is odd   {n = 3 + p1 + p2} ( n-3 is even, so that recall second case.)

For convenience, prime numbers under 10^5 can be initialized.

Edited by author 03.12.2012 03:00

Edited by author 03.12.2012 03:00
Re: Hint..
prove it :)
Re: Hint..
Posted by dangminhhieu78 2 Aug 2015 20:58
If he could proof it, he would get 1 thousand million dollar

Edited by author 02.08.2015 20:59
Re: Hint..
Posted by PO 12 Jan 2019 19:52
> if n is odd   {n = 3 + p1 + p2} ( n-3 is even, so that recall second case.)

IMO this is wrong. 85 = 2 + 83 is the counter-case.

> For convenience, prime numbers under 10^5 can be initialized.

this way too big. :)

Edited by author 12.01.2019 19:53

Edited by author 12.01.2019 19:54