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-   -   Oops - New Prime! (M49 related) (https://www.mersenneforum.org/showthread.php?t=20830)

dleclair 2016-01-20 22:31

[URL="http://www.npr.org/sections/thetwo-way/2016/01/20/463725028/ready-for-prime-time-a-number-with-20-million-plus-digits"]NPR[/URL]

Uncwilly 2016-01-21 00:51

[QUOTE=Madpoo;423244]The surprising bit were the 2300+ DC exponents assigned to new users, anywhere from 39.5M up to just below 44M. Those have a better chance of finishing since the time involved is smaller. DC is pretty far behind the first-time checks so fingers crossed that helps clear the backlog a tiny bit.[/QUOTE]Also, since they are so much faster, they should see results in a more reasonable time. This would encourage them to stick around.

Batalov 2016-01-21 00:55

[QUOTE=dleclair;423275][URL="http://www.npr.org/sections/thetwo-way/2016/01/20/463725028/ready-for-prime-time-a-number-with-20-million-plus-digits"]NPR[/URL]
[quote]Curiously, Cooper says that the computer's notification system also failed the four other times it found a record number.[/quote][/QUOTE]
"Surely You're Joking, Mr. Feynman!"

cuBerBruce 2016-01-21 01:15

[QUOTE=Madpoo;423259]Sure, one worker with one core could probably test M49 faster than a month, but what if you had 4 workers each testing exponents around that same size? Still < 1 month for each of them?[/QUOTE]

Yep. I tried running four M49-size exponents at the same time, each using one core. The ETAs were 29-30 days. When running fewer than four, the speed (per exponent) went up. With 3 exponents at 1 core each, I was getting 23-24 days for the ETAs. For 1 exponent on 1 core, the ETA was down to about 16.5 days.

Dubslow 2016-01-21 01:16

[QUOTE=cuBerBruce;423290]Yep. I tried running four M49-size exponents at the same time, each using one core. The ETAs were 29-30 days. When running fewer than four, the speed (per exponent) went up. With 3 exponents at 1 core each, I was getting 23-24 days for the ETAs. For 1 exponent on 1 core, the ETA was down to about 16.5 days.[/QUOTE]

Massive, massive memory bottleneck. Quite a shame, really.

LaurV 2016-01-21 01:32

[QUOTE=dleclair;423275][URL="http://www.npr.org/sections/thetwo-way/2016/01/20/463725028/ready-for-prime-time-a-number-with-20-million-plus-digits"]NPR[/URL][/QUOTE]
[QUOTE]If you printed each digit 1 mm wide [of the 22 million digits number], the number would stretch for more than a half marathon's 13.2 miles.[/QUOTE]:davar55: This guy even can't count! That is a full marathon number! And a little bit more. :razz:

The real utility of such big primes, and the extraordinarily rewarding part of searching for them, is that when one is found, you can laugh the lungs out of you reading what some idiots comment on the web...

(yeah, I know some other sites show a comment similar to this, but is not plagiarized from there, it was me who put it there too!)

Dubslow 2016-01-21 01:51

[QUOTE=LaurV;423293]:davar55: This guy even can't count! That is a full marathon number! And a little bit more. :razz:

The real utility of such big primes, and the extraordinarily rewarding part of searching for them, is that when one is found, you can laugh the lungs out of you reading what some idiots comment on the web...

(yeah, I know some other sites show a comment similar to this, but is not plagiarized from there, it was me who put it there too!)[/QUOTE]

A full marathon is more than 26 miles. A half marathon is 13.1 miles, which is 21.4 kilometers, and at 1mm digits the prime is 22.3 kilometers long, so aside from being less than .1 mile off, the statement you quote is correct.

science_man_88 2016-01-21 02:01

[QUOTE=Dubslow;423294]A full marathon is more than 26 miles. A half marathon is 13.1 miles, which is 21.4 kilometers, and at 1mm digits the prime is 22.3 kilometers long, so aside from being less than .1 mile off, the statement you quote is correct.[/QUOTE]

I walked, wii fit free "ran" and paced 19.9 km one day it's quite far I could do about 2.5 laps of my neighbourhood with that distance.

ewmayer 2016-01-21 02:06

[QUOTE=LaurV;423293]:davar55: This guy even can't count! That is a full marathon number! And a little bit more. :razz:

The real utility of such big primes, and the extraordinarily rewarding part of searching for them, is that when one is found, you can laugh the lungs out of you reading what some idiots comment on the web...[/QUOTE]

LaurV is latest victim of the quick-maths analog of the "You shoud lern too spell before opening your mouth, maroon!" effect. :) Happened to me just last night, literally while waiting for my post on "estimated odds of finding another M-prime between the largest 2" to go through, I realized I'd neglected to account for the fact that most of the candidates in that range have already been TF-eliminated or 1st-time-LL-tested.

BTW, the OMG-I-am-an-idiot headslap moment one frequently has just after clicking "submit" on a numbers-involving post has a formal name: "the aftermath".

Dubslow 2016-01-21 02:08

[QUOTE=ewmayer;423297]LaurV is latest victim of the quick-maths analog of the "You shoud lern too spell before opening your mouth, maroon!" effect. :) Happened to me just last night, literally while waiting for my post on "estimated odds of finding another M-prime between the largest 2" to go through, I realized I'd neglected to account for the fact that most of the candidates in that range have already been TF-eliminated or 1st-time-LL-tested.

BTW, the OMG-I-am-an-idiot headslap moment one frequently has just after clicking "submit" on a numbers-involving post has a formal name: "the aftermath".[/QUOTE]

It happens to me on far more things than just numbers :razz:

Mark Rose 2016-01-21 02:36

[YOUTUBE]tlpYjrbujG0[/YOUTUBE]


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