20200807, 11:25  #397 
Sep 2010
Weston, Ontario
179_{10} Posts 
I have added indicators for intervals #19#21 to my list. I have also decided that the above mentioned "beachhead" is far too ambitious. My intended beachhead is now interval #21. I am still in the process of verifying my new list of Leyland numbers which runs from L(102999,10) to L(149999,10), 337553864 terms. A worthwhile guide is that for d > 11, L(d1,10) is (likely) the smallest (base ten) ddigit term. The sortedbymagnitude list will allow me to directly look up the Leyland number index of any (x,y) term in that range. It will also, of course, provide the seed (x,y) pairs needed to generate the ABC files for my intervals.

20200807, 18:59  #398 
"Norbert"
Jul 2014
Budapest
2^{5}×3 Posts 
Another new PRP:
1678^28479+28479^1678, 91839 digits. 
20200814, 09:40  #399 
Sep 2010
Weston, Ontario
10110011_{2} Posts 

20200820, 11:50  #400 
Sep 2010
Weston, Ontario
179 Posts 

20200821, 21:05  #401  
Sep 2010
Weston, Ontario
B3_{16} Posts 
Quote:
I've put a compilation of smally solutions (y <= 1000) here. 

20200826, 05:06  #402 
Sep 2010
Weston, Ontario
179_{10} Posts 

20200906, 09:21  #403 
Sep 2010
Weston, Ontario
10110011_{2} Posts 
I decided to take my sieving of interval #21 to 1e10 and that still has a couple of days to go. In the meantime I am pfgwing recently assigned (and already sieved) interval #28 [L(148999,10)  L(149999,10)] and have now my first hit therein:
33845^26604+26604^33845 is 3PRP! I'm not sure factordb.com will PRP this for me. I noticed that Norbert's PRPTop submissions for a couple of his larger Leyland primes has a list of primePRPs from prime 2 to 11. Which brings me to ask why pfgw default reports only 3PRPs. How does one get it to do other primes? Is it even necessary? 
20200906, 14:07  #404  
"Mark"
Apr 2003
Between here and the
1011100111100_{2} Posts 
Quote:


20200920, 03:54  #405  
Sep 2010
Weston, Ontario
10110011_{2} Posts 
Quote:
That completes interval #14 which I did in two parts. The second (larger Leyland numbers) part, which I did first, ended up with 69 PRPs. Because the first (smaller Leyland numbers) part started off with roughly an identical quantity (~21919300) of Leyland numbers as the second part, I was expecting at least 69 PRPs in it as well, but it ended up with only 57 PRPs. I'm well on my way to completing (likely by October 12th) intervals #15, #16, and #28. 

20200925, 19:05  #406 
"Mark"
Apr 2003
Between here and the
2^{2}×1,487 Posts 
I have written a small program that converts pxp's text list of x^x+y^x primes/prps into an html table that has sortable columns. The source and html that it generates is attached.

20200925, 21:32  #407  
Sep 2010
Weston, Ontario
179 Posts 
Quote:
Code:
g++ xyyx.cpp o xyyx xyyx.cpp:60:56: warning: format specifies type 'unsigned long long *' but the argument has type 'long *' [Wformat] if (sscanf(ptr, "%u %llu %u (%u,%u)", &index, &leylandNumber, &length, &x, &y) != 5) I can probably run this every time I update my a094133.txt document and share it here. A couple of minor issues: Christ van Willegen and Jens Kruse Andersen have lost their surnames and GĂ¶ran Hemdal has lost the umlauted o (I assume that it is visible in the .txt version). 

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