# Damn, thought I was onto something... **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [February 4, 2009, 3:22am UTC](https://boards.straightdope.com/t/damn-thought-i-was-onto-something/484364 "2009-02-04T03:22:19Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [February 4, 2009, 3:22am UTC](https://boards.straightdope.com/t/damn-thought-i-was-onto-something/484364/1 "2009-02-04T03:22:19Z")
IIRC, one of the great mathematical goals is a Prime Number Generator. (you do know what a prime number IS…don’t you?) in this thread: > **[Mathematical (re)discovery of mine...](https://boards.straightdope.com/sdmb/showthread.php?t=496985)** > > Except for 2 and 3, all prime numbers are one more or one less than some multiple of 6: A…B…C…D…E…F 0…1…2…3…4…5 6…7…8…9…10…11 12…13…14…15…16…17 18…19…20…21…22…23 24…25…26…27…28…29 30…31…32…33…34…35 36…37…38…39…40…41 42…43…44…45…46…47 ... I (re)discovered the general form of prime numbers: except for 2 and 3, all primes are of the form (6\*X)+or- 1. What is X? Running this simple formula in my head, and later on paper, I figured X must itself be prime. If we designate 1,2, and 3 as quasi-prime (not true primes as they are NOT of the form (6\*X)+ or- 1), then this formula does indeed start generating new primes: COLUMN 1 COLUMN 2 (6_1)+/-1= 5 and 7 (6_2)+/-1= 11 and 13 (6_3)+/-1= 17 and 19 (6_4)+/-1= 23, not 25 (6_5)+/-1= 29 and 31 (6_6)+/-1= 37, not 35 (6_7)+/-1= 41 and 43 (6_8)+/-1= 47, not 49 (6_9)+/-1= 53, not 55 (6_10)+/-1=59 and 61 AFAIK, when X is prime, the formula does indeed generate a new prime(col1), yet some primes are generated by the formula when X is NOT prime. Am I missing something? ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [February 4, 2009, 8:21am UTC](https://boards.straightdope.com/t/damn-thought-i-was-onto-something/484364/2 "2009-02-04T08:21:28Z")
6x+1 or 6x-1? Don’t you mean 4x+1 or 4x-1? This rule holds for all odd prime numbers, even 1 and 3. x=0, p=1 x=1, p=3,5 x=2, p=7 x=3, p=11,13 x=4, p=17 x=5, p=19 etc. ---
**Author:** ![Indistinguishable](https://avatars.discourse-cdn.com/v4/letter/i/90ced4/32.png) [@Indistinguishable](https://boards.straightdope.com/u/Indistinguishable)\ **Post date:** [February 4, 2009, 8:26am UTC](https://boards.straightdope.com/t/damn-thought-i-was-onto-something/484364/3 "2009-02-04T08:26:03Z")
> [@Quartz](#): > > 6x+1 or 6x-1? Don’t you mean 4x+1 or 4x-1? This rule holds for all odd prime numbers, even 1 and 3. Yes, these are both pretty trivial rules, and there are a million like them: 4x plus or minus 1 (except for 2) because otherwise you’d be divisible by 2. 6x plus or minus 1 (except for 2 and 3) because otherwise you’d be divisible by 2 or divisible by 3. 10x plus or minus 1 or 3 (except for 2 and 5) because otherwise you’d be divisible by 2 or divisible by 5. These things are a dime a dozen, I’m afraid. ---
**Author:** ![Indistinguishable](https://avatars.discourse-cdn.com/v4/letter/i/90ced4/32.png) [@Indistinguishable](https://boards.straightdope.com/u/Indistinguishable)\ **Post date:** [February 4, 2009, 8:27am UTC](https://boards.straightdope.com/t/damn-thought-i-was-onto-something/484364/4 "2009-02-04T08:27:37Z")
> [@Enola\_Straight](#): > > Am I missing something? Yes. The very next case: 6 \* 11 - 1 = 65, which isn’t prime, even though 11 is prime. For an example using plus instead of minus, 6 \* 19 + 1 = 115, which, again, isn’t prime, even though 19 is. ---
**Author:** ![Aspidistra](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aspidistra/32/3894_2.png) [@Aspidistra](https://boards.straightdope.com/u/Aspidistra)\ **Post date:** [February 4, 2009, 8:40am UTC](https://boards.straightdope.com/t/damn-thought-i-was-onto-something/484364/5 "2009-02-04T08:40:17Z")
Also, 9 is not prime ---
**Author:** ![Knowed\_Out](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/knowed_out/32/7380_2.png) [@Knowed\_Out](https://boards.straightdope.com/u/Knowed_Out)\ **Post date:** [February 4, 2009, 2:01pm UTC](https://boards.straightdope.com/t/damn-thought-i-was-onto-something/484364/6 "2009-02-04T14:01:42Z")
It used to be thought that prime numbers and perfect numbers were related, [but not always.](http://en.wikipedia.org/wiki/Perfect_number) ---
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [February 4, 2009, 11:24pm UTC](https://boards.straightdope.com/t/damn-thought-i-was-onto-something/484364/7 "2009-02-04T23:24:54Z")
> [@Knowed\_Out](#): > > It used to be thought that prime numbers and perfect numbers were related, [but not always.](http://en.wikipedia.org/wiki/Perfect_number) Exploring that link, I came across the Goldbach Conjecture, stating that any even number greater than 2 is the sum of two primes. This is unproven. REALLY? All Primes larger than 2 are Odd. Even number + odd number = odd number Even number + even number = even number Odd number + odd number = even number THEREFORE… (P\>2)+(P\>2)=even number! _RIGHT?_😕 ---
**Author:** ![Lemur866](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lemur866/32/434_2.png) [@Lemur866](https://boards.straightdope.com/u/Lemur866)\ **Post date:** [February 4, 2009, 11:34pm UTC](https://boards.straightdope.com/t/damn-thought-i-was-onto-something/484364/8 "2009-02-04T23:34:18Z")
You just proved that the sum of two primes has to be even. That’s different than proving that every even number is the sum of two primes.