20120911, 21:32  #45 
Mar 2006
Germany
37×79 Posts 
On occasion of the recent finds I've updated my pages for Home Prime Base 10 (49) and the EuclidMullinSequence.

20121123, 17:49  #46 
Mar 2006
Germany
37×79 Posts 
I've extended the page with First odd k with Sophie Germain from n=4000 to n=10000.

20121124, 06:44  #47 
Romulan Interpreter
Jun 2011
Thailand
262C_{16} Posts 
I don't really understand what the yellow values in that table are. The comment say "jumping champion  the highest k so far", but this can't be. For some of them there are very easy to find higher k's. For example for n=10, the table say k=141, in yellow. A oneliner in pari stops indeed at 141:
Code:
gp > k=1; until(isprime(a)&&isprime(b), k++; print(k", "a=1024*k1", "factorint(a)",\t"b=2048*k1", "factorint(b))) 2, 2047, [23, 1; 89, 1], 4095, [3, 2; 5, 1; 7, 1; 13, 1] 3, 3071, [37, 1; 83, 1], 6143, Mat([6143, 1]) 4, 4095, [3, 2; 5, 1; 7, 1; 13, 1], 8191, Mat([8191, 1]) 5, 5119, Mat([5119, 1]), 10239, [3, 1; 3413, 1] 6, 6143, Mat([6143, 1]), 12287, [11, 1; 1117, 1] .... snip many lines .... 139, 142335, [3, 2; 5, 1; 3163, 1], 284671, [23, 1; 12377, 1] 140, 143359, [23, 2; 271, 1], 286719, [3, 1; 31, 1; 3083, 1] 141, 144383, Mat([144383, 1]), 288767, Mat([288767, 1]) gp> So, what exactly is the meaning of the yellow cells? 
20121124, 10:29  #48 
Mar 2006
Germany
37×79 Posts 
The table shows the first odd kvalue of Rieseltype numbers a=k*2^n1 and b=k*2^(n+1)1 for which a and b both primes (Sophie Germains).
The yellow values are the highest in this table, so for n=10 k=141 is highest of all lower n and every time a kvalue is higher than the last yellow, it is marked yellow as new highest. 
20121124, 10:59  #49 
Romulan Interpreter
Jun 2011
Thailand
2^{2}×7×349 Posts 
Ah, got it now. Not very useful, however...

Thread Tools  
Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
News  gd_barnes  Conjectures 'R Us  303  20211001 20:47 
News  gd_barnes  No Prime Left Behind  253  20210815 05:26 
Other news  Cruelty  Riesel Prime Search  41  20100308 18:46 
The news giveth, the news taketh away...  NBtarheel_33  Hardware  17  20090504 15:52 
News  KEP  Riesel Base 3 Attack  4  20081217 11:54 