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#26 2012-06-06 05:21:12

TheDude
Member
Registered: 2007-10-23
Posts: 361

Re: Unique Relationship to find prime numbers

It's interesting, but your method could be improved to produce all odd numbers except the primes with a single formula.  Instead of starting from x = 6y + 5 and x = 6y + 7, use x = 2y + 1.  You eventually get a formula of

n = 4qb + 2b + 4pq + 2p + 2q + 1

Where b, p, q are integers and 0 < b, q and 0 <= p


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#27 2012-06-06 05:26:15

hasaneweidah
Member
Registered: 2012-06-01
Posts: 19

Re: Unique Relationship to find prime numbers

Wow very cool, did you improved it?

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#28 2012-06-06 05:31:54

TheDude
Member
Registered: 2007-10-23
Posts: 361

Re: Unique Relationship to find prime numbers

I just took your basic idea and modified it.  The equations you used, x = 6y + 5 and x = 6y + 7, simply generate all odd numbers except those divisible by 3.  But the equation x = 2y + 1 generates all odd numbers.  This has two benefits: 1) You don't have to check if a number is missing from the list because it's divisible by 3 to make sure it is prime, and 2) You only have one possibility for m and a: m = 2p + 1 and a = 2q + 1.  This lets you generate your list from one formula instead of four.


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#29 2012-06-06 05:34:47

hasaneweidah
Member
Registered: 2012-06-01
Posts: 19

Re: Unique Relationship to find prime numbers

It's great work. Would you like to write it in the form of article with your name and I will add it to my search as your improvement to the equations?

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#30 2012-06-06 06:09:04

TheDude
Member
Registered: 2007-10-23
Posts: 361

Re: Unique Relationship to find prime numbers

You can take credit for it, you did the hard part and I'm not interested in publishing or anything like that.


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#31 2012-06-06 06:17:11

hasaneweidah
Member
Registered: 2012-06-01
Posts: 19

Re: Unique Relationship to find prime numbers

OK. just give me your name

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#32 2012-06-06 07:28:15

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Unique Relationship to find prime numbers

Hi;

So

it is easy now to see that n is always odd and composite.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#33 2012-06-06 07:39:03

TheDude
Member
Registered: 2007-10-23
Posts: 361

Re: Unique Relationship to find prime numbers

Indeed, and also readily apparent that all composite odd numbers are covered.

Edit: In fact, you can even simplify it further to (2p + 1)(2q + 1) = 4pq + 2p + 2q + 1, 0 < p, q.

Last edited by TheDude (2012-06-06 07:42:01)


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#34 2012-06-06 08:08:30

hasaneweidah
Member
Registered: 2012-06-01
Posts: 19

Re: Unique Relationship to find prime numbers

TheDude and bobbym very nice work.

TheDude I added it into search just I want to write your name so please send it to my e-mail or write it here.

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#35 2012-06-20 10:02:44

hasaneweidah
Member
Registered: 2012-06-01
Posts: 19

Re: Unique Relationship to find prime numbers

bobbym and The dude, I have reached to general equation that gives all prime numbers only.

14.0zz0/2012/06/20/21/961041611

before 14 add 'www'

after 0zz0 add '.com'

and after 961041611 add '.png'

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#36 2012-06-21 00:23:36

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Unique Relationship to find prime numbers

Hi hasaneweidah;

I am getting a DNS error, when I try that link.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#37 2012-06-21 05:06:31

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: Unique Relationship to find prime numbers

Hi bobbym

Maybe you typed it out wrong. It should be:

www14.0zz0.com/2012/06/20/21/961041611.png


“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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#38 2012-06-21 05:12:06

hasaneweidah
Member
Registered: 2012-06-01
Posts: 19

Re: Unique Relationship to find prime numbers

sorry guys, it's wrong approach. But I will do my best to reach to the final equation

Good luck for you ,,,

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#39 2012-06-21 15:44:29

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Unique Relationship to find prime numbers

Hi anonimnystefy;

Thanks for the link but there are still some kinks to iron out in that equation.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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