mersenneforum.org mfaktX result: "found 1 factor for M"
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 2012-12-20, 14:54 #1 swl551     Aug 2012 New Hampshire 23·101 Posts mfaktX result: "found 1 factor for M" I'm just double checking some assumptions I've made in the data stored in results.txt. I see this in a results.txt row "found 1 factor for M......"; Is it possible this phrase would ever say "found 2 factor for M....." (or any other number > 1)? Thanks
 2012-12-20, 15:17 #2 LaurV Romulan Interpreter     Jun 2011 Thailand 2×3×5×313 Posts Yes. IIRC, the message "Mxxx has a factor yyy bla bla bla" is said when a factor is found, and the class is finished, and at the end (when the bitlevel or the full assignment is finished, depending on the split) it says how many factors were found. So, if there are two factors (or more) at the same bitlevel, or even in the same class, and if your .ini file or command line switches does not instruct the mfaktc to stop immediately after a factor is found, then yes, at the end you will get "Found 2 (3, 4, etc) factors for Mxxx bla bla". Edit: indeed, I just checked for "Factor=N/A,20882179,5,65" and the result file says: Code: UID: LaurV/pinch_tf, M20882179 has a factor: 208821791 [TF:5:65:mfaktc 0.19 75bit_mul32] UID: LaurV/pinch_tf, M20882179 has a factor: 1336459457 [TF:5:65:mfaktc 0.19 75bit_mul32] UID: LaurV/pinch_tf, M20882179 has a factor: 6970714517160387449 [TF:5:65:mfaktc 0.19 75bit_mul32] UID: LaurV/pinch_tf, M20882179 has a factor: 459124775652761 [TF:5:65:mfaktc 0.19 75bit_mul32] UID: LaurV/pinch_tf, M20882179 has a factor: 866401606711 [TF:5:65:mfaktc 0.19 75bit_mul32] UID: LaurV/pinch_tf, M20882179 has a factor: 76331482436884447 [TF:5:65:mfaktc 0.19 75bit_mul32] UID: LaurV/pinch_tf, M20882179 has a factor: 24059653120999 [TF:5:65:mfaktc 0.19 75bit_mul32] UID: LaurV/pinch_tf, M20882179 has a factor: 279081857409627487 [TF:5:65:mfaktc 0.19 75bit_mul32] UID: LaurV/pinch_tf, M20882179 has a factor: 173188864790271367 [TF:5:65:mfaktc 0.19 75bit_mul32] UID: LaurV/pinch_tf, found 9 factors for M20882179 from 2^ 5 to 2^65 [mfaktc 0.19 75bit_mul32] No guarantee they are all prime :P (they are all known factors, I picked the most convenient exponent from James' site, by number of known factors). Last fiddled with by LaurV on 2012-12-20 at 15:41
2012-12-20, 15:20   #3
swl551

Aug 2012
New Hampshire

23·101 Posts

Quote:
 Originally Posted by LaurV Yes. IIRC, the message "Mxxx has a factor yyy bla bla bla" is said when a factor is found, and the class is finished, and at the end (when the bitlevel or the full assignment is finished, depending on the split) it says how many factors were found. So, if there are two factors (or more) at the same bitlevel, or even in the same class, and if your .ini file or command line switches does not instruct the mfaktc to stop immediately after a factor is found, then yes, at the end you will get "Found 2 (3, 4, etc) factors for Mxxx bla bla".

Thank you!

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