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Old 2014-08-28, 13:12   #166
Wick
 
Nov 2012

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Code:
17033^53-1 = 319391252920161429560547697830623021848733 * 33330520337724660774026719117185864816084423298503770977448713371276795862990739368941333958579469564572049892835902778824236910135478940052210949429612763456195776438992014984777
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Old 2014-08-30, 16:02   #167
chris2be8
 
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I won't have finished ECM'ing 7643^59-1 when 13147^53-1 starts LA (I'm using a GPU and 1 core for ECM so it takes a while). So I'll reserve some small fry to do while ECM finishes:
21407^47-1
60259^43-1
61799548199^17-1

Chris
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Old 2014-09-07, 15:43   #168
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Reserving one more for ECM, to be followed by SNFS if that fails:
3251^61-1

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Old 2014-09-08, 05:49   #169
Wick
 
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Code:
13331^59-1 = 80755497159734947485059693840546839 * C205
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Old 2014-09-11, 11:19   #170
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http://www.lirmm.fr/~ochem/opn/i_51_2000_101.txt
This file is the intersection of the composites encountered in the proof of the bounds
\Omega(N) >= 2\omega(N)+51, N > 10^2000, and \omega(N) >= 101.
So if you get a factor, it helps for all 3 proofs.
Also, as we branch on the smallest prime for omega(N) >= 101 and on the largest prime for N > 10^2000, a composite in the file is likely to derive from a prime that is the only available prime at some point of the execution of the algorithm. So these composites are bottlenecks.
The amount of ECM varies from "maybe not so much" to "a lot, really" for 6115909044841454629^17-1.

Last fiddled with by Pascal Ochem on 2014-09-11 at 11:21
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Old 2014-09-11, 17:19   #171
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Quote:
Originally Posted by chris2be8 View Post
Reserving one more for ECM, to be followed by SNFS if that fails:
3251^61-1

Chris
It won't need SNFS:
Code:
********** Factor found in step 2: 9937677757664476852904593531609640792365970218237
Found probable prime factor of 49 digits: 9937677757664476852904593531609640792365970218237
Probable prime cofactor 4933435390111026832796658137713158696690314285678621089166487442937825189905611449855687999637684794906443696039349871186136410748647635964240864254651 has 151 digits
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Old 2014-09-14, 15:25   #172
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Quote:
Originally Posted by Pascal Ochem View Post
The amount of ECM varies from "maybe not so much" to "a lot, really" for 6115909044841454629^17-1.
What is the lowest amount of ECM any will have had? Should we start at T30, T35, T40 or higher to look for factors?

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Old 2014-09-16, 16:02   #173
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You can start at T40. And thank you for the factors you already obtained.
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Old 2014-09-17, 15:32   #174
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I've reached the point in mwrb2000.txt where the next most cost effective number would be 6115909044841454629^17-1 or 11^311-1 (depends how fast 6115909044841454629^17-1 would be as an octic). They are both out of my range so I'll stop there.

It would still be worth running ECM against the rest of it, there is probably some low hanging fruit waiting to be found.

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Old 2014-09-17, 17:23   #175
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Code:
6853807^29-1 = 112590938436045242392801854371922664426393 * C151
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Old 2014-09-24, 05:34   #176
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Code:
22787^47-1 = 4543639013539669426613291598225427127 * 62549558218207738524332749889176473882724629210639329124410765199872180435689083679828086455715730270805552655974310311001299087407579824443318458077069317807742131
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