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Old 2021-03-21, 12:21   #1009
Happy5214's Avatar
Nov 2008
The Alamo City

23×97 Posts

Originally Posted by garambois View Post
I managed to get your program to work.

The abundance of 30^55440 is validated in 22 seconds on my computer with the program in C. (Very old CPU from 2011).
The validation is almost instantaneous with my python program.
For base 30, testing all even exponents from 2 to 10,000 takes 6 minutes 30 seconds with the C program and 55 seconds with my python program.

I'm sorry I don't know what's going on.
I know the C should be a lot faster.
Moreover, I cannot understand the program in C !

Please find in attached file my program in python.
I tried to comment on it to make it clearer.
I hope my comments will be enough for you ...
It was nowhere near quick enough. I rewrote the sigma calculation to use the well-known closed-form formula instead of a loop, and that significantly sped it up. The test you used (base 30 from 2 to 10k) now takes 2.2 seconds on my Kubuntu Focus. The new version is attached. I also found that s(30^(80640*3)) is in fact abundant, which is backed up by work I've posted on FactorDB.

Edit: The same range takes 6.3 seconds on my 2009-era Core 2 Quad desktop, which is a more similar comparison to your computer. I'd say that blows your script out of the water.
Attached Files
File Type: gz powerAbundance_1.tar.gz (1.4 KB, 49 views)

Last fiddled with by Happy5214 on 2021-03-21 at 12:30 Reason: Desktop timing
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