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2022-08-19, 08:44   #584
pxp

Sep 2010
Weston, Ontario

5×47 Posts

Quote:
 Originally Posted by japelprime I do not want to do uncontrolled Sieve range or solo work out of the blue here. To messy. Any gabs to close maybe if that will help ?
All of the gaps in my table are just as you see them. That is from 150000 decimal digits to 300000 decimal digits and greater than 305000 decimal digits, with the exception of the four from 386434 to 386642 decimal digits. That is, they are organized by decimal-digit size. I think Norbert Schneider still uses an (x,y) search approach to his prime finds but just limits his ranges to be sufficiently large. He has not shared which ranges he has actually tried. I don't know how Gabor Levai found his very large primes but I suspect that his approach is closer to my own, which is to organize Leyland (x,y) pairs by digit-size and sieve them that way. For example, the (x,y) pairs of Leyland numbers with exactly one million digits are, in order of increasing size, tabled here.

 2022-09-04, 09:03 #585 NorbSchneider     "Norbert" Jul 2014 Budapest 112 Posts Another new PRP: 38442^38531+38531^38442, 176658 digits.
2022-09-12, 22:08   #586
japelprime

"Erling B."
Dec 2005

1478 Posts

PXP your data are good document to hold things in perspective. Thanks
Here we have a prime chart as I find here in the latest data replay from PXP. PXP It is upgrade what I see you have been doing earlier. Easier to estimate the Sieve range that have been done until now. I am not sure if I have all data,
Attached Files
 Leyland Prime_Sept22.pdf (753.5 KB, 59 views)

Last fiddled with by japelprime on 2022-09-12 at 22:26

 2022-09-13, 05:31 #587 pxp     Sep 2010 Weston, Ontario 5×47 Posts The chart looks good. Why are some of the points orange?
2022-09-13, 15:28   #588
pxp

Sep 2010
Weston, Ontario

5×47 Posts

Quote:
 Originally Posted by pxp Why are some of the points orange?
Never mind. My reproduction here shows that they are likely the points (currently 37) discovered in 2022.
Attached Thumbnails

2022-09-13, 23:26   #589
japelprime

"Erling B."
Dec 2005

103 Posts

Quote:
 Originally Posted by pxp Never mind. My reproduction here shows that they are likely the points (currently 37) discovered in 2022.
Yes Correct.

 2022-09-22, 18:15 #590 lghu   Nov 2019 19 Posts A new PRP (currently pfgw64 -f only): 105098^61113+61113^105098 503014 digit, index: 6153473043, discoverer Miklos Levai
 2022-10-04, 07:38 #591 lghu   Nov 2019 19 Posts I found another PRP: 101863^84922+84922^101863 [502085 digit] index: 6132803185
 2022-11-04, 15:31 #592 lghu   Nov 2019 238 Posts The next PRP index: 6136565930. pxp: This is enough for you?
 2022-11-07, 20:59 #593 NorbSchneider     "Norbert" Jul 2014 Budapest 12110 Posts lghu: I like to know what is the new leyland PRP. For me is PRP index no help. Are you from Hungary, can you speak hungarian? I am from Hungary and also search Leyland primes.
2022-11-07, 23:56   #594
pxp

Sep 2010
Weston, Ontario

EB16 Posts

Quote:
 Originally Posted by lghu The next PRP index: 6136565930. pxp: This is enough for you?
No. Back in March I created a dictionary of Leyland (x,y) pairs from (999999,10) to (1000999,10), sorted by magnitude and preceded by its Leyland-number index (21588818851 to 21628375832). So I can look up the (x,y) pair if the index is within that bound. But I have no similar dictionary for your index, which corresponds to ~502250 decimal digits.

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