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#1 |
Nov 2003
2·1,811 Posts |
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[The following post is about 281*2^628898-1, a prime found by Cruelty in December 2007.]
Cruelty, a nice and important prime because k=281 was the only k<300 with no primes with more than 100k bits! Next target: 200k bits, there are 4 Ks with no primes larger than 200k bits: k=109, 221, 233, and 283. All reserved by you !! The one with the minmax prime is k=221: n=104846. Last fiddled with by Kosmaj on 2012-05-05 at 06:16 |
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#2 |
Nov 2003
1110001001102 Posts |
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The 4 Ks < 300 with minmax (smallest largest) primes are now:
k=221, n=104846 k=109, n=141227 k=283, n=149351 k=233, n=179992 All tested to 600k, and all currently reserved by Cruelty. |
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#4 |
Nov 2003
2×1,811 Posts |
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Update on k<300 minmax primes:
Code:
k largest prime 233 179992 13 233207 191 240802 249 251036 The largest primes of all other Ks have 300k digits or more. k=283 was removed from the top of the list by Cruelty. Its largest prime was at n=149351, but now it's at n=1702599. The previous status can be found here. |
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#5 |
Nov 2003
2·1,811 Posts |
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I moved this discussion to a separate thread.
In the meanwhile the following primes were found 233*2^1700734-1 by Cruelty, July 2010 13*2^2606075-1 by Curtis, December 2011 13*2^2642943-1 by Curtis, February 2012 Therefore, there are now only three k<300 which largest known prime has less than 300k binary bits: k=191 at n=240802, tested up to n=4.2M k=249 at n=251036, tested up to n=1.1M k=151 at n=263895, tested up to n=2.9M All other k<300 have largest known primes with more than 300k bits. Last fiddled with by Kosmaj on 2012-05-05 at 22:57 |
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#6 |
"Curtis"
Feb 2005
Riverside, CA
122448 Posts |
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151 263895 is under 300k bits.
I count 7 others below 500k bits: 7 372897 37 341365 43 399767 225 491135 239 356300 275 398928 295 389903 -Curtis |
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#7 |
Nov 2003
2·1,811 Posts |
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Curtis, thanks for listing other candidates and specially for the correction about k=151, I missed that one.
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Thread Tools | |
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