20140513, 23:53  #12  
"Mark"
Apr 2003
Between here and the
13332_{8} Posts 
Quote:
...or someone else could take ownership. EDIT (S.B.): That's exactly what Andrey did a few years ago: http://xyyxf.at.tut.by/primes.html#0 Last fiddled with by Batalov on 20140514 at 00:19 

20140514, 00:13  #13 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
2^{3}·5·227 Posts 
[2000140000, 11200] range is done. One PRP I had found two years ago, and now, the rest:
Code:
11^36442+36442^11, 37951(decimal digits) (2012) 33^21262+21262^33, 32287 63^20018+20018^63, 36020 76^24787+24787^76, 46620 92^32907+32907^92, 64623 98^27819+27819^98, 55394 105^34684+34684^105, 70103 117^26870+26870^117, 55573 128^29007+29007^128, 61124 128^32001+32001^128, 67433 129^28468+28468^129, 60085 131^31870+31870^131, 67478 143^39070+39070^143, 84209 157^29934+29934^157, 65733 163^26530+26530^163, 58690 181^22300+22300^181, 50347 200^20373+20373^200, 46879 
20140514, 08:31  #14 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
2378_{16} Posts 

20140514, 12:16  #15 
Account Deleted
"Tim Sorbera"
Aug 2006
San Antonio, TX USA
10AB_{16} Posts 
FWIW, the result of sieving the range [1250115000, 200115000] to 1657571 (which took a few hours on a core)
https://www.dropbox.com/s/5plhnqg5hwqtbn8/xyyx.7z As a rough estimate: 700,000 candidates (guess of how many will remain after sieving; currently 720,880 remaining) at 40 seconds (timings for PFGW tests ranged from 26 to 58 seconds) per candidate per core makes this range an 80 day job for a quad core Haswell. I don't want to make that much of a commitment right now, but someone can use my sieve file as a starting point. 
20140514, 17:22  #16  
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
2^{3}×5×227 Posts 
Quote:
Code:
1033^16254+16254^1033, 48992 1263^19898+19898^1263, 61712 1265^19732+19732^1265, 61211 1271^17368+17368^1271, 53913 1338^15377+15377^1338, 48076 1417^15754+15754^1417, 49647 1456^19909+19909^1456, 62976 1508^17691+17691^1508, 56230 1537^18832+18832^1537, 60012 1576^19021+19021^1576, 60821 1638^15437+15437^1638, 49620 1684^16495+16495^1684, 53219 1741^19546+19546^1741, 63345 1828^16589+16589^1828, 54113 1839^17156+17156^1839, 56008 1845^16636+16636^1845, 54334 1850^18879+18879^1850, 61681 1897^16710+16710^1897, 54777 1908^17605+17605^1908, 57755 1943^15222+15222^1943, 50058 

20140515, 15:49  #17 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
2^{3}·5·227 Posts 
And one PRP to rule them all:
15^328574+328574^15 (386434 digits) 
20140515, 16:38  #18 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
9080_{10} Posts 
Reserving [40001330000, 1117]

20140515, 19:54  #19 
Jan 2005
Minsk, Belarus
400_{10} Posts 
Why not ...20]?

20140515, 20:36  #20 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
2378_{16} Posts 
Because it is more work? ;)
Maybe later. (19 and 20 are particularly heavy and 20^330000 >> 17^330000) Someone can relatively easily do the y=18. Free idea! Anyone? 
20140515, 23:50  #21 
(loop (#_fork))
Feb 2006
Cambridge, England
6,353 Posts 
I am running Y=18, should make it to 300k by the end of the month unless I've screwed up my calculations somewhere.
Last fiddled with by fivemack on 20140515 at 23:51 
20140516, 17:34  #22 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
21570_{8} Posts 
[40001330000, 1117] is done. Three PRPs:
11^255426+255426^11 12^47489+47489^12 (previously known) 15^328574+328574^15 
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