20050526, 23:56  #111 
"Jason Goatcher"
Mar 2005
3·7·167 Posts 
I'm going to try n=106.

20050527, 02:16  #112  
"Jason Goatcher"
Mar 2005
3·7·167 Posts 
Quote:
I'm hoping I'm reading the text file correctly. I'm reserving n=153. Last fiddled with by jasong on 20050527 at 02:20 

20050527, 03:35  #113 
Aug 2004
Melbourne, Australia
2^{3}·19 Posts 
New largest...
My family went out for the day so I borrowed their computers, and discovered the octoproth:
8923480720155 187 k*2^n+1 has 70 digits. Took three computers about 8 hours to sieve. Several seconds to PRP. 
20050527, 08:16  #114 
Aug 2004
Melbourne, Australia
2^{3}×19 Posts 
Update
Some newies:
1520564179575 106 462410580975 107 New most wanted: n=108. Searched upto k=10000000000000 so far. Looking again at the 'weights' of the bases... the next big peak is at n=202. Looks like this would be a good base to search for a new largest octoproth. Searched upto k=240385459755 so far. 
20050527, 19:25  #115 
"Jason Goatcher"
Mar 2005
110110110011_{2} Posts 
none for 153, but I found a bunch I missed with 105, at least 10, not sure of the total.

20050528, 18:36  #116 
Jun 2003
Oxford, UK
1,933 Posts 
Brilliant
Hats off to Dougy, Axn1 et al. for taking this challenge a lot further than I had thought possible.
It does appear as if there are an infinite number of octoproths, based on the exponential growth for n completed to date. I love numbers, I love playing with infinity, it is like squirting petrol onto a bonfire from a squeezy bottle (dangerous not to be recommended, but I did that as a child, so infinity seems a tad tame really). I love the sequence that starts 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,2.... Has anyone listed this on Sloane's? Regards Robert 
20051226, 16:22  #118 
"Sander"
Oct 2002
52.345322,5.52471
29×41 Posts 
With one pc available during the christmas weekend i decided to search a bit further for first occurrences for octoproths. I've extended the lower limmits for all N with no octoproth < 141. I'll sieve a bit more overnight.
Code:
108 15000000000000 10049232509295 109 5000000000000 2535547302735, 3896979101085 110 10000000000000 111 5000000000000 3412332425985 114 5000000000000 2810303334615 115 5000000000000 1767457796805, 2535344519085, 2748688738965, 2792226666585, 3427082197245, 3641677619775 116 10000000000000 117 10000000000000 8822382927435 118 7556065630365 6935662533645 119 5000000000000 121 5000000000000 122 1000000000000 123 1000000000000 124 1000000000000 125 1000000000000 126 1000000000000 127 1000000000000 128 1000000000000 129 1000000000000 131 500000000000 132 500000000000 133 500000000000 134 500000000000 136 500000000000 137 500000000000 138 5000000000000 139 500000000000 140 500000000000 
20051231, 15:56  #119 
Nov 2005
2×7×13 Posts 
I've used newpgen with the outputs from the octo_fast executable for n upto 49. Is this correct? What's the exact list of steps to generate octoproths using your tool?
Last fiddled with by nibble4bits on 20051231 at 15:57 
20051231, 17:31  #120  
"Sander"
Oct 2002
52.345322,5.52471
29·41 Posts 
Quote:
You can use (win)pfgw to test these numbers. Read the whole thread to learn how to create an ABC file. I've found octoproths for all N's below 135 and a few more above that. 3 more remain to be found below n=141 Code:
108 15000000000000 10049232509295 109 5000000000000 2535547302735, 3896979101085 110 20000000000000 15987840863295 111 5000000000000 3412332425985 114 5000000000000 2810303334615 115 5000000000000 1767457796805, 2535344519085, 2748688738965, 2792226666585, 3427082197245, 3641677619775 116 50000000000000 27808601284905, 48874747118295 117 10000000000000 8822382927435 118 7556065630365 6935662533645 119 7624791125805 6947969463435 121 15000000000000 10860421305525, 11007840039945, 122 7549086697425 6770724125445 123 15000000000000 14795373071115 124 20793700201365 15857166234525, 17317349329155, 18814945517745 125 30000000000000 21000707492835, 22110474424815, 26230498255815, 28051609645605 126 15000000000000 10208767082535, 13988965055835 127 30000000000000 24755390572485 128 75000000000000 70201312304025 129 5000000000000 4473550622625 131 29670452060865 29423194631775 132 10000000000000 8247597994965 133 10000000000000 8866435688265 134 15000000000000 5925199200375, 9900362493945 135 50000000000000 136 50000000000000 43732992858225, 49020296591265 137 20000000000000 16328957487255 138 45000000000000 139 10000000000000 2536458109485, 9744953313285 140 40000000000000 

20051231, 18:32  #121 
Aug 2005
Brazil
2×181 Posts 
Is there some way to resume the sieve using octo?
BTW, what are those octo_deep and octo_fast you're talking about? I only saw one executable, octo.exe!? 
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