20210320, 17:01  #1002  
"Garambois JeanLuc"
Oct 2011
France
1010101100_{2} Posts 
Quote:
I don't know how to work on numbers of several hundred thousand digits with the C language ? But if any of you can do this, the program must be very easy to write. And then maybe we will find suitable exponents for bases 3, 5 or 7. (I also launched the execution of calculations for base 7.) Quote:
It has nothing to do with whether a number is masculine or feminine. We say "la moitié d'un nombre" (half of a number), because "moitié" is feminine and "le double d'un nombre" (the double of a number), because "double" is masculine ! We understand better why automatic translation is so difficult ! 

20210320, 19:35  #1003  
"Alexander"
Nov 2008
The Alamo City
2^{3}·97 Posts 
Quote:
Quote:
Code:
g++ O2 o powerAbundance powerAbundance.cc lgmp lgmpxx 

20210320, 20:55  #1004 
"Ed Hall"
Dec 2009
Adirondack Mtns
2^{4}×257 Posts 

20210320, 22:51  #1005 
"Curtis"
Feb 2005
Riverside, CA
11·461 Posts 
13^64 up through 13^70 are now C120 or bigger and can be updated.
I expect to get the rest of base 13 turned orange this week. Sorry for the delay! Edit: please leave them reserved to me; I plan to get all of base 13 to 140 digits. Last fiddled with by VBCurtis on 20210320 at 22:52 
20210321, 10:47  #1006  
"Garambois JeanLuc"
Oct 2011
France
2^{2}×3^{2}×19 Posts 
Quote:
Quote:
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 ... 

20210321, 10:55  #1007  
"Garambois JeanLuc"
Oct 2011
France
2^{2}·3^{2}·19 Posts 
Quote:
Thank you very much ! There is really no problem with the delay : it's the same for me. At the moment I am working on the abundance of index 1 terms of the bases with very large exponents as explained in the posts above. And this mobilizes my CPU and I can no longer advance the calculations of the complete sequences of the project ! 

20210321, 12:16  #1008 
Oct 2006
Berlin, Germany
1163_{8} Posts 
I take bases 58 2310 30030 510510 9699690 82589933.

20210321, 12:21  #1009  
"Alexander"
Nov 2008
The Alamo City
2^{3}×97 Posts 
Quote:
Edit: The same range takes 6.3 seconds on my 2009era Core 2 Quad desktop, which is a more similar comparison to your computer. I'd say that blows your script out of the water. Last fiddled with by Happy5214 on 20210321 at 12:30 Reason: Desktop timing 

20210321, 13:22  #1010 
"Garambois JeanLuc"
Oct 2011
France
684_{10} Posts 

20210321, 14:22  #1011  
"Garambois JeanLuc"
Oct 2011
France
2^{2}×3^{2}×19 Posts 
Quote:
Many, many thanks ! 8 seconds now for the program written in C against 55 seconds for the python program ! Congratulations ! So I'm going to stop my three python programs for bases 3, 5 and 7 and start your program in C. I'm just going to add a hard drive backup of the exponents that generate abundant index 1 terms. It is wonderful to all work together on this problem. If we find what we are looking for for a base which is a prime number, we will have worked very well ! On your side, let me know if you manage to make the program even faster : this is what happened to me several times with my program in python ! But this time around, I think it's going to be very difficult to gain more speed ... 

20210321, 15:06  #1012 
"Garambois JeanLuc"
Oct 2011
France
2^{2}×3^{2}×19 Posts 
Please I am unable to add the correct line of code to write this in bold below in my save file called "power_abundant_exponents" :
30 55440 (base + exponent) As you can see, I only manage to write the exponent i and not the base, because I don't know the equivalent for "base" of "% d" that works for i. I do not know the type of "base". By the way, "% d" does not seem correct to me for the variable i, because it can be very large ! But it seems to work ! Code:
if (n > partial) { fff = fopen ("power_abundant_exponents", "a"); if (fff == NULL) printf("Impossible to open file !"); else { fprintf (fff, "%d\n",i); fclose (fff); cout << base.get_str() << "^" << i << " is abundant !" << endl; }; } else { // cout << base.get_str() << "^" << i << " is not abundant." << endl; } 
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