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Old 2005-08-28, 03:41   #4
wblipp's Avatar
May 2003
New Haven

3·787 Posts

For about a week someone with an email address that begins "jasong@" has been using the ElevenSmooth ECM Server. If that is you, then one possibility is to continue doing what you are doing. There are also other ECM Servers that you could connect to. If you have the new ECM Client, you can even set up multiple servers and tell the client what percentage to work on each server.

In a separate email you have asked about using ECM to work on one of the numbers from the composite page. People do that from time to time, but it isn't a good use of resources. The numbers posted there have already had ECM work, and are most effectively worked on using the Number Field Sieve, such as GGNFS.

If you want to contribute ECM work to the search for odd perfect numbers, the must useful work would be to connect to the "Most Wanted" ECM Server at . Most of the assignments here are looking for 55 digit factors of 19193-1, one of two large factorizations needed to prove there are no odd perfect numbers under 10500. These tasks take about 2 Ghz hours each, and use moderately large amounts of memory. If that is a problem, you could connect to the "More Wanted" ECM Server at These assignments are looking for 40 to 45 digit factors of numbers less than 300 digits with no known factors. These numbers have the potential to become roadblocks in the future.

Running an ECM client is easy and helpful, but it provides about as much excitement as watching paint dry. People often want a more hands on experience when helping a project. A common way to achieve this greater sense of involvment is to pick one or more numbers that become "your" numbers, to set up the input files yourself, to start up the ecm process manually, to check the log files visually, and to personally compose messages about factors found and curves run. If this appeals to you, the easiest place to start is probably the Cunningham pages in this forum. You can pick from among all the unfinished Cunningham numbers, you can see how much work has previously been done, and you can post results directly in the fora. If you want to do that and also work on numbers of some interest to, pick numbers of the form pq-1, where p and q are both odd primes.

Last fiddled with by wblipp on 2005-08-28 at 03:42
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