A few months ago I decided that since finding a Mersenne prime is extremely unlikely, and I don't have a good chance of finding any huge prime, looking for factors of small unfactored Mersenne might be more rewarding.
I didn't really expect to see anything so soon, but this evening the following showed up: ECM found a factor in curve #692, stage #1 Sigma=6367806696755784, B1=3000000, B2=300000000. UID: gsnyder/P4-1.8GHz, M2161 has a factor: 117194366114889271070074059667667222873 If you like your numbers with commas, the 39-digit factor is 117,194,366,114,889,271,070,074,059,667,667,222,873 Below is the prime, and confirmation that the stated number is a factor 2^2161-1 33559897820263818973328366672316900265106281616071323131740682958447\ 23020031958525072257855411838339438755855397849883223173639723336826\ 11818963633898026623796104377359695298969744747862271248381904782724\ 01410540964741344128534170717980528805095132859691435473682974821527\ 66967600674003723458926658836927870073420383036522947349982262463351\ 94612046602490095977412175612268046379624188025365954888124792184015\ 09808402680269806694634108721940647535981318000009670121757594834487\ 38769988427120579195343840353631293116733882263414527206998792512969\ 24724690039255472123968177736567130060069578721022002761288047769658\ 671765880606929736241866036307612925951 (2^2161-1)%117194366114889271070074059667667222873 0 M2161 was number 10 on the list of smallest Mersenne numbers with no known factor. I am happy!! Gerry (the lucky) -- mailto:[EMAIL PROTECTED] _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers