20200701, 23:24  #375  
Sep 2010
Weston, Ontario
163 Posts 
Quote:
I noticed that the help file had sieve start "3" as the default, suggesting perhaps that p2 might be an out of range argument. As a result, I reworked my shared pages to exclude even L(x,y). That brings the number of terms per page down from ~11000 to ~7300. The first three lines of my first page are now: Code:
ABC $a^$b$c*$b^$a // Sieved to 3 102503 5888 +1 80340 64561 +1 Last fiddled with by pxp on 20200701 at 23:27 Reason: added link 

20200702, 15:43  #376 
Sep 2009
2×3^{3}×5×7 Posts 
rogue, can you post a sample file that works for you. Then pxp can run that to check his binary is OK, then change 1 thing at a time until it's doing what he wants. I've found that starting from a working example makes problem solving much easier.
Chris 
20200702, 16:46  #377 
"Mark"
Apr 2003
Between here and the
17·347 Posts 
Apparently I did not do a "make clean" before I did the make. The attached should work with the proper ABC file.
I also found an issue in avx_powmod that only impacts nonWindows builds. That is also fixed. Code:
./xyyxsieve ixyyx.in p3 P1e6 xyyxsieve v1.5, a program to find factors numbers of the form x^y+y^x Sieve started: 3 < p < 1e6 with 1324 terms (78917 <= x <= 283782, 23 <= y <= 78832) (expecting 1219 factors) Sieve completed at p=1000193. Processor time: 13.87 sec. (0.00 sieving) (0.98 cores) 503 terms written to xyyx.pfgw Primes tested: 78512. Factors found: 821. Remaining terms: 503. Time: 14.16 seconds. 
20200702, 18:08  #378 
Sep 2010
Weston, Ontario
243_{8} Posts 
Code:
mm5:~ pxp$ cd /Users/pxp/Desktop/rogue mm5:rogue pxp$ ./xyyxsieve i386434.txt p3 P2e9 xyyxsieve v1.5, a program to find factors numbers of the form x^y+y^x Sieve started: 3 < p < 2e9 with 7203 terms (78911 <= x <= 1283705, 2 <= y <= 78900) (expecting 6834 factors) p=5957291, 4.586K p/sec, 6757 factors found at 1.52 sec per factor, 0.3% done. ETC 20200703 06:54 p=10411189, 4.588K p/sec, 6768 factors found at 5.53 sec per factor, 0.5% done. ETC 20200703 02:52 p=14994013, 4.595K p/sec, 6775 factors found at 8.68 sec per factor, 0.7% done. ETC 20200703 01:09 p=24406297, 4.597K p/sec, 6785 factors found at 12.15 sec per factor, 1.2% done. ETC 20200702 23:34 p=29201503, 4.594K p/sec, 6789 factors found at 15.19 sec per factor, 1.5% done. ETC 20200702 23:08 p=34041223, 4.597K p/sec, 6794 factors found at 12.15 sec per factor, 1.7% done. ETC 20200702 22:48 p=38899507, 4.573K p/sec, 6798 factors found at 15.18 sec per factor, 1.9% done. ETC 20200702 22:33 p=43805231, 4.583K p/sec, 6800 factors found at 30.36 sec per factor, 2.2% done. ETC 20200702 22:21 
20200702, 19:43  #379  
"Mark"
Apr 2003
Between here and the
17·347 Posts 
Quote:
You can use ^C to stop at any time. The program will finish processing the current chunk, then save and exit. If 2e9 isn't deep enough you can start sieving again using ixyyx.pfgw. You will not need to use p as it will grab the initial prime from the input file. 

20200703, 17:20  #380 
Sep 2010
Weston, Ontario
243_{8} Posts 
Code:
Processor time: 22549.57 sec. (1.62 sieving) (0.99 cores) 333 terms written to xyyx.pfgw Primes tested: 98222288. Factors found: 6870. Remaining terms: 333. Time: 22668.14 seconds. http://chesswanks.com/num/LLPHbdl/386434.txt http://chesswanks.com/num/LLPHbdl/386435.txt http://chesswanks.com/num/LLPHbdl/386436.txt They contain 317, 325, and 303 terms, respectively. I think I can PRPtest any one of these in under a week and I intend to try in the near future. But first I will generate more sieved pages. I ran multiple terminal windows to generate the three files. My initial attempt at this ran off the same xyyxsieve, little realizing that the ongoing xyyx.pfgw files overwrote each other. So I ended up cloning the folder containing xyyxsieve and reran each terminal window off its own folder. I suppose a future version of xyyxsieve could output a .pfgw file with a name that matches the input file name. 
20200703, 17:35  #381  
"Mark"
Apr 2003
Between here and the
17×347 Posts 
Quote:
You can override the name of the output file by using o and specifying the file name. 

20200704, 02:57  #382  
Romulan Interpreter
Jun 2011
Thailand
2·11·397 Posts 
Quote:
To have the plus at the end, just use "\1 \2 +1" in the "replace with" box. For who didn't hear about regular expressions, this translates to "if you find two groups of any number of digits each, alone on the row (i.e. no other text, the ^ and $ signs represent beginning and end of the row) which are between parenthesis and separated by c comma, extract the the two groups in two different strings (called \1 and \2, this is what the internal parenthesis do, in the "find what" string) and rearrange them according with the "replace with" box, possibly adding some text (the +1 and spaces) around them". That's all. No magic. Or, actually, Magic! You still need to add the header line "ABC blah blah" by hand (i.e. typing ) Edit: picture (Notepad++ used for exemplification) because Mathjax messed my expression, I know there was a way to block this, which Serge wrote here in the past, but we forgot the tag... was it "noeval", or what? One more observation, in Notepad++ the regex search/replace is undoable (if you mess the expression, just press undo and retry till you learn the right way) Last fiddled with by LaurV on 20200704 at 04:20 

20200706, 12:45  #383  
Sep 2010
Weston, Ontario
163 Posts 
Quote:
I don't of course expect to find a PRP. It strikes me as unlikely that any of the 45 pages will yield one. But don't let that put you off willing to look. Every eliminated page brings us closer to that eventual new largestknown Leyland prime. 

20200710, 11:38  #384 
Just call me Henry
"David"
Sep 2007
Cambridge (GMT/BST)
13130_{8} Posts 
Am I correct in thinking you are sieving each digit length separately? Is there any advantage in doing this? How does combining digit lengths affect sieve speed?

20200710, 15:24  #385 
Sep 2010
Weston, Ontario
163 Posts 
Sorting Leyland numbers by digitlength — more properly, by absolute magnitude — has been my obsession from the getgo. Mark hacked the existing program to accommodate any Leylandnumber input file, including my sorted ones.

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