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 2020-11-21, 16:06 #507 Alfred     May 2013 Germany 83 Posts p54 with ecm and B1 = 3e6 Caught this p54 while searching for a brilliant 199-digit number. Code: Input number is 9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999992027 (199 digits) Using B1=3000000-3000000, B2=5706890290, polynomial Dickson(6), sigma=3:1452677002 Step 1 took 0ms Step 2 took 2813ms ********** Factor found in step 2: 423160190219167918418888831508389397512846550243914177 Found prime factor of 54 digits: 423160190219167918418888831508389397512846550243914177 Prime cofactor 23631712602314236460375363605669880057528256019179586483958332029245798546518655036308640681338947369725232833261868840557864887635516265827697051 has 146 digits
 2021-01-03, 00:20 #508 fivemack (loop (#_fork))     Feb 2006 Cambridge, England 24·3·7·19 Posts L1513 finished 202-digit GNFS done locally Code: Tue Aug 4 13:05:29 2020 R0: -1028224595046037683938542391736748085046 Tue Aug 4 13:05:29 2020 R1: 4848130132767804170091793 Tue Aug 4 13:05:29 2020 A0: 648878061894436523327775882840696551093747592165 Tue Aug 4 13:05:29 2020 A1: 13245849346295954315426797465107710625703 Tue Aug 4 13:05:29 2020 A2: -376642136328230129661761611055571 Tue Aug 4 13:05:29 2020 A3: -9454281508658701649335711 Tue Aug 4 13:05:29 2020 A4: 116526330703266438 Tue Aug 4 13:05:29 2020 A5: 428485680 Tue Aug 4 13:05:29 2020 skew 67545908.29, size 5.912e-20, alpha -8.299, combined = 2.961e-15 rroots = 3 ... sieve Q=40M..375M in 1078087489 thread-seconds ... Sat Nov 21 21:26:59 2020 matrix is 63151125 x 63151542 (22228.8 MB) with weight 5094240601 (80.67/col) Sat Nov 21 21:26:59 2020 sparse part has weight 4816732203 (76.27/col) Fri Jan 1 15:23:55 2021 lanczos halted after 247423 iterations (dim = 63151125) Sat Jan 2 20:57:21 2021 p70 factor: 4493695606770472637867321927044598060152799561314346673366564420496931 Sat Jan 2 20:57:21 2021 p133 factor: 2148834568682702094964376360162085149774220051591587827359563815630236626372124575110661016995807683695989368484857539018308408221331
 2021-01-30, 01:06 #509 Stargate38     "Daniel Jackson" May 2011 14285714285714285714 2×52×13 Posts Another P4x at
 2021-01-30, 02:03 #510 swishzzz   Jan 2012 Toronto, Canada 59 Posts Very close to the same digital length composition for two 3-ways Code: 10^199 + 23173 = 224433735459577392947020227278055347817380372899653241 * 677166587753085022008921622519679777457914400728666270398231717 * p83 10^199 + 24181 = 125246337159352133080104859058799976828033420210335353 * 4292155836263037911802907280773029436191511910550793277991358423 * p83
 2021-02-01, 22:25 #511 unconnected     May 2009 Russia, Moscow 50028 Posts Lucky find for near-repdigit number (74*10^283+7)/9: Code: Using B1=3000000, B2=5706890290, polynomial Dickson(6), sigma=1:949432216 Step 1 took 9528ms Step 2 took 4729ms ********** Factor found in step 2: 1182219105908711587346038374813771128564935992167 Found prime factor of 49 digits: 1182219105908711587346038374813771128564935992167 Prime cofactor 472167911435767590384937592650265763333570374651435418184918818066214429283320719814902198706039980988613407949105532565490068110752657746342543 has 144 digits
 2021-02-02, 09:24 #512 MisterBitcoin     "Nuri, the dragon :P" Jul 2016 Good old Germany 2×13×31 Posts Found this little factor with using the wrong programm. Code: W1030492381 has a factor: 440348557948741296977 [TF:68:69:mfaktc 0.21 barrett76_mul32_gs] found 1 factor for W1030492381 from 2^68 to 2^69 [mfaktc 0.21 barrett76_mul32_gs] There isnt anyone interessted on factors for Wagstaff numbers for that range?
 2021-02-16, 02:22 #513 sean     Aug 2004 New Zealand 2×3×37 Posts 50-digit factor of 95!+25 with B1=1e6 I don't see many 50 digits factors with B1=1e6 ... Code: Run 178 out of 200: Using B1=1000000, B2=1045563762, polynomial Dickson(6), sigma=2726828695 Step 1 took 2276ms Step 2 took 1436ms ********** Factor found in step 2: 20819759916248446572812979296981961157835787899653 Found probable prime factor of 50 digits: 20819759916248446572812979296981961157835787899653 Probable prime cofactor 2944668849437874913553507825327499221600601795476762700186109016306167187 has 73 digits
 2021-04-23, 15:04 #514 bur   Aug 2020 167 Posts I finally got a dedicated factoring machine running and its first real task was factoring a C138 from aliquot 30081984:1920 Code: 7973712480336027352229719413187897894070666267573380770460370574546256076128028667504883219837711672619409359725392220343873377 = 715215026635608879010699711940390170306392146448359506114304683758700914 * 1114869260765477729412719553078740045166565405836068797 I don't know the total time as it was interrupted when I lost the SSH connection (didn't know about tmux then), sometime between 12 and 24 hours... The second was the last remaining co-factor of 1022^162-1 which the base 1022 Wieferich prime 163 belongs to: Code: Total factoring time = 16160.6690 seconds ***factors found*** P69 = 561453556809307449235709634757896494545317098972093987639522375815171 P58 = 4466710490347773515450994252634894622624341053542443215433

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