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Old 2020-11-20, 22:57   #50
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"Ed Hall"
Dec 2009
Adirondack Mtns

2×23×79 Posts

Originally Posted by chris2be8 View Post
There have been a load of a few thousand digit numbers added to factordb recently. When factordb tries to factor them it runs ECM, which often finds a composite factor which is the product of most of the smallish factors of the number. That's probably the source of most of the small numbers with many factors.

And the reason why there are over 121000 PRPs under 3000 digits!

Try picking a few and clicking "More information" to see what it's a factor of and following the chain. That should show you where stuff is being added now.

At least the explanations provide an acceptable reason for the huge inpouring. The PRPs I hadn't noticed! Might be time to shift in that direction for a while. I'll have to think about that. I had a set of scripts to work through a range across several machines, but I'd have to figure out which one was the server and how I ran them. I think I had an RPi acting as server.
Originally Posted by penlu View Post
This is how I upload my results, but I advise not to do this because you might create many new IDs -- I set my stuff to upload only the largest factor found.

I realize this probably increases the load on factordb since for small composites the cofactor is often under the 19-digit autofactor threshold. But it seems to result in a higher clearance rate. The incentive is a little perverse?
I used to do the same - only return the largest prime. But, currently I'm sending the whole set of found factors back. I did just hit the limit, though, so I might have to rework my scripts to only the largest again.

I'm also running Colab sessions and don't worry about them because they are only single threaded and unique IP'ed. All of my scripts presently do the full circle of retrieve composite - factor - return results - repeat. But, I plan to look into retrieving several, factoring all and returning all at once. I'm not sure there's a method for larger composites, though. They may have to be retrieved one at a time if you want randomness.
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