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-   -   The "one billion minus 999,994,000" digits prime number (https://www.mersenneforum.org/showthread.php?t=20568)

 R.D. Silverman 2015-10-26 11:16

[QUOTE=LaurV;413802]Won't suffice, both are higher than n^2 (in the first case 9, second case 121). What he calls "Pn2". His theorem is true, but not useful to generate primes, as Serge said, it will need to store primes to 10^500M.[/QUOTE]

One also needs to look at the computational complexity of FINDING a partition that
satisfies the condition on d. It is non-trivial.

BTW, a similar scheme was looked at and rejected a number of years ago in this very forum.....

 R.D. Silverman 2015-10-26 14:51

[QUOTE=R.D. Silverman;413811]One also needs to look at the computational complexity of FINDING a partition that
satisfies the condition on d. It is non-trivial.

BTW, a similar scheme was looked at and rejected a number of years ago in this very forum.....[/QUOTE]

I see that a couple of my posts have been deleted.

However, doing so exemplifies the typical hypocrisy of this group, since whoever did it allowed the
following comment from the crank who started this thread

"BTW, thank you for being one of the few intelligent posters to this thread. "

in response to a (correct!) comment from alpertron.

 R.D. Silverman 2015-10-26 14:55

[QUOTE=axn;413803]You've accidentally left out a critical part of the theorem (because of poor typography on OP's part, mind you)[/QUOTE]

Yes.

However this correct observation also shows another deficiency in the OP's 'algorithm'.

His method fails to present a method for partitioning the set of primes such that d HAS
the required property.....

Can you say "combinatorial search"?????

 ewmayer 2015-10-26 18:52

[QUOTE=LaurV;413802]Won't suffice, both are higher than n^2 (in the first case 9, second case 121). What he calls "Pn2". His theorem is true, but not useful to generate primes, as Serge said, it will need to store primes to 10^500M.[/QUOTE]

Ah, gotcha (thx to axn, as well). So we're left with another 'mathematically true, but practically useless' scheme of the kinds discussed in e.g. Crandall & Pomerance or any similar NT reference which includes computational-feasibility analyses.

 jasong 2015-10-28 23:30

I understand very little of this thread, but I think it would be helpful for the people who still have a level head to review the thread on the other forum that led to this one. I know next to nothing about number theory, but at the bottom of the first page of that thread is an interesting statement seeming to vouch for a1call's credentials. Maybe it's faked, I have no idea, but it's something to consider.

 a1call 2015-10-28 23:58

the credentials are based on the Theorem 1 That I disclosed to one of the members. That's what the vouch is about. The same theorem has since been posted here and has been judged useless for the most part on this board.
The thread on the other board has progressed further on the topic though. Thank you for note [B]jasong[/B].
If anyone is interested in my credentials I am mechanical designer by trade (specializing in Parametric CAD design) but have had computer maintenance and programming as well electronic design experience through my decades of work experience.
I am a semi-regular member on the cosmoquest board which might be an indication of my interests.

My CV is available for all to see here:

 R.D. Silverman 2015-10-29 00:15

[QUOTE=a1call;414139]the credentials are based on the Theorem 1 That I disclosed to one of the members. That's what the vouch is about. The same theorem has since been posted here and has been judged useless for the most part on this board.
The thread on the other board has progressed further on the topic though. Thank you for note [B]jasong[/B].
If anyone is interested in my credentials I am mechanical designer by trade (specializing in Parametric CAD design) but have had computer maintenance and programming as well electronic design experience through my decades of work experience.
I am a semi-regular member on the cosmoquest board which might be an indication of my interests.

My CV is available for all to see here:

Keeps piling on the crankometer points.......

 ewmayer 2015-10-29 00:39

[QUOTE=a1call;414139]My CV is available for all to see here:[/QUOTE]

I think I speak for just about everyone here when I say that no one cares about your bragsheet credentials, only whether your proposed method is potentially useful. The latter point has been settled to the satisfaction of everyone who has replied to this thread and is also not a known crank or ignoramus. Time for you to shut up and go read any of the references which have been mentioned, about various other 'prime finding' methods with similar properties to yours. Or add 'too credentialed to ever again undertake learning anything new' to your CV, if you prefer.

 LaurV 2015-10-29 07:48

@OP: Man, with so much programming skill, why the fruit you need somebody to program the algorithm for you? Large integer and FFT float libraries are plenty, for free, you just "#include <bhahblah>" and start computing.

P.S. I am in full agreement with the two guys who posted just before.

 a1call 2015-10-31 20:44

The following 183 digit prime was found using formulation using the Theorem 1, without scripting and programming.
Is that of any significance considering the method?
Are there any other formulas which can give comparable results without programming?

The number of digits is about a dozen less than the maximum of what the free version of Wolfram Alpha accepts.

268247424057311445389468276509855422892624146761442207989329055956776521156436821116123624436462260510842892838582894073662704750945426649505938377042214898386145890456554863200575291

[URL]http://www.wolframalpha.com/input/?i=268247424057311445389468276509855422892624146761442207989329055956776521156436821116123624436462260510842892838582894073662704750945426649505938377042214898386145890456554863200575291+prime%3F[/URL]

Credits to Wolfram Alpha for doing the arithmetic.

Thank you for your time and replies.

 Batalov 2015-10-31 21:07

[QUOTE=a1call;414450]The following 183 digit prime was found using formulation using the Theorem 1, without scripting and programming.
Is that of any significance considering the method?
[/QUOTE]
Nope. You have shown no proof that it was in fact found by "this method", "without scripting and programming"
[QUOTE=a1call;414450]
Are there any other formulas which can give comparable results without programming?
[/QUOTE]
Of course, yes.
Press [URL="http://factordb.com/index.php?query=1777171*2^n-1&use=n&n=800&VP=on&VC=on&EV=on&OD=on&PR=on&PRP=on&U=on&perpage=20&format=1&sent=Show"]here[/URL] and you will find a few primes that were not known a few seconds ago, because nobody cared for primes this small.
Here is the link, spelled out: