Gratuitous factors thread - Page 47

Alfred · 2020-11-21, 16:06

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

fivemack · 2021-01-03, 00:20

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

Stargate38 · 2021-01-30, 01:06

Super lucky find from this number

Code:

01/29/21 19:58:08 v1.35-beta @ LAPTOP-ONGC39AN, prp45 = 363663840350383283238303865573198932342477697 (curve 39 stg2 B1=250000 sigma=2489289353 thread=6)
01/29/21 19:58:10 v1.35-beta @ LAPTOP-ONGC39AN, Finished 45 curves using Lenstra ECM method on C293 input, B1=250K, B2=gmp-ecm default
01/29/21 19:58:10 v1.35-beta @ LAPTOP-ONGC39AN, current ECM pretesting depth: 25.86

swishzzz · 2021-01-30, 02:03

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

unconnected · 2021-02-01, 22:25

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

MisterBitcoin · 2021-02-02, 09:24

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?

sean · 2021-02-16, 02:22

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

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2021-02-02, 09:24	#512
MisterBitcoin "Nuri, the dragon :P" Jul 2016 Good old Germany 11×73 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?