[QUOTE=Batalov;400581]I tried different options for submitting a factor, and all of them don't list the finder (me :-)
I am now simply submitting a single line

into manual results form - either on mersenne.ca or mersenne.org (while logged in!).

I tried pasting the whole ECM output - the result is the same (or worse - not parsed out).

It doesn't matter to me. It is a valid contender for the [URL="http://primes.utm.edu/top20/page.php?id=49"]Mersenne cofactor[/URL] top20; this does matter. The cofactor is proven before submitting, of course.[/QUOTE]

I can see in the server logs where you posted that result at 2015-04-21 @ 17:08:12 UTC. George or James can probably give better guidance on why it might accept the factor but not log the result text as submitted. It may have been formed in such a way it couldn't parse all of it, or something... and now that it's a known factor it won't accept any other submissions for it, I think. But never fear, it can be manually done I'm sure.

I think for small and very old factors, this is fine (for them to be anonymous).
In Ye Goode Olde Days, factors were immaterial - only primes were the goal of the project, so they bore no name.
In fact, that's fine even for larger factors (including mine); I mean fine for me.

However, because large crowds started making a sport out of factoring alone and they need some encouragement ("look, here is _[I]my[/I]_ factor"; "hey, my factor is bigger than yours!") and they need their name attached to a factor. Which is a fair price for the amount of (GPU) work (and electricity) they put into this effort. They [I]will[/I] want to find a bigger factor and they [I]will[/I] run their computers some more. If all they will be getting out of the project would be the heated house and a constant hum from the computer, they may fall off pretty fast.

[QUOTE=Batalov;400619]
However, because large crowds started making a sport out of factoring alone and they need some encouragement ("look, here is _[I]my[/I]_ factor"; "hey, my factor is bigger than yours!") and they need their name attached to a factor. Which is a fair price for the amount of (GPU) work (and electricity) they put into this effort. They [I]will[/I] want to find a bigger factor and they [I]will[/I] run their computers some more. If all they will be getting out of the project would be the heated house and a constant hum from the computer, they may fall off pretty fast.[/QUOTE]
+1 (me, me, me, sexy me-me....) :razz:

[QUOTE=Batalov;400619]I think for small and very old factors, this is fine (for them to be anonymous).
In Ye Goode Olde Days, factors were immaterial - only primes were the goal of the project, ...[/QUOTE]Why you want to downgrade those poor little factors when they are precisely the thing that everyone is searching for; PRIMES! It's not the size of the primes that matters, it's what you do with them.

[size=1]It's my prime and I'll stroke it as fast and as often as I want. And besides, I was only cleaning it. Honest.[/size]

:rofl: :goodposting:

[QUOTE=Batalov;400573]One more:
[URL="http://factordb.com/index.php?query=2%5E35339-1"]M35339[/URL] = 5776625742089 · 291148630508887 · 7028028455954046211351 · [COLOR="Blue"]4153830438466899077960892137[SUB]<28>[/SUB] · P10562[/COLOR][/QUOTE]
And one more:
[URL="http://factordb.com/index.php?query=2%5E41681-1"]M41681[/URL] = 1052945423 · 16647332713153 · [COLOR="Blue"]2853686272534246492102086015457[SUB][/SUB] · [URL="http://primes.utm.edu/primes/page.php?id=119809"]P12495[/URL][/COLOR][/QUOTE]

This time I found a big PRP:

(2^1790743-1)/(146840927*158358984977*3835546416767873* 20752172271489035681) is a 539014-digit PRP. See [url]http://www.mersenne.ca/exponent/1790743[/url]

[QUOTE=alpertron;404786]This time I found a big PRP:

(2^1790743-1)/(146840927*158358984977*3835546416767873* 20752172271489035681) is a 539014-digit PRP. See [url]http://www.mersenne.ca/exponent/1790743[/url][/QUOTE]

:w00t: Congrats!

[QUOTE=axn;404804]:w00t: Congrats![/QUOTE]

Thanks, it appears that the cofactor of M1790743 is now 35th in the ranking of the top PRP list:

[url]http://www.primenumbers.net/prptop/prptop.php?page=1#haut[/url]

The 300th (probably) completely Mersenne number factored known is M675977

The cofactor (2[sup]675977[/sup]-1)/(1686378749257*7171117283326998925471) has 203456 digits.

You can see it at: [url]http://www.mersenne.ca/exponent/675977[/url]

List of PRP Mersenne cofactors: [url]http://www.mersenne.ca/prp.php?show=1&min_exponent=1&max_exponent=10%2C000%2C000[/url]

The 306th known probably-fully-factored Mersenne exponent is [URL="http://www.mersenne.ca/exponent/151013"]M151013[/URL]

It is a semiprime, whose smaller factor 61157791169561859593299975690769 was discovered October 28.

This is too large for primality certification. All probable-prime cofactors for exponents 63703 and below have been proven prime (274 out of the 306), while all the larger ones are only (highly) probably prime.

The list of known Mersenne primes and fully-factored or probably-fully-factored exponents can be found at [url]http://www.mersenne.ca/prp.php[/url]



The 305th was [URL="http://www.mersenne.ca/exponent/5233"]M5233[/URL], with 5 factors plus a cofactor. The 304th was [URL="http://www.mersenne.ca/exponent/822971"]M822971[/URL], with 3 factors + cofactor.

The 303rd was [URL="http://www.mersenne.ca/exponent/5240707"]M5240707[/URL], the current record holder. It is a semiprime, whose smaller factor 75392810903 was discovered a long time ago by trial-factoring, but was not PRP tested until late July of this year.