Sierpinski/ Riesel bases 6 to 18 - Page 11

robert44444uk · 2007-01-27, 03:26

Ok, here are the next few candidates for 16, all tested to n=4295. Last k tested was 47805

27592
27838
28593
28918
29445
30250
30397
31347
31912
32161
32350
32556
32673
33661
33771
34528
34543
35257
35320
35548
35818
35845
36735
37372
38440
38562
38776
39322
39337
39781
40000
40410
41530
42052
42376
42717
42745
43368
43398
43468
43485
44035
44131
44490
45306
45712
46471
46528
47176
47298
47395
47482
47616

robert44444uk · 2007-01-27, 10:50

And here is the last batch of Sierpinski 16, tested to n=5098

47818
48697
48772
48976
49386
49860
50166
50863
50865
51171
51427
52072
53226
53653
53941
54610
55306
55611
55846
55897
56866
57238
57795
57867
58582
58791
58855
59890
60070
60343
60541
60891
61617
61687
62802
63390
63405
63411
63853
64518
64620
65077
65127
65397
65536 square
65623

robert44444uk · 2007-01-27, 11:01

In post 112, k=40000 is square

Citrix · 2007-01-27, 11:22

Quote:

Originally Posted by robert44444uk

In post 112, k=40000 is square

You did not exclude numbers divisible by 16

robert44444uk · 2007-01-27, 12:05

I will reserve those above k=60000 and take them quite high

robert44444uk · 2007-01-27, 12:07

Quote:

Originally Posted by Citrix

You did not exclude numbers divisible by 16

True, can you spot them and weed them out

robert44444uk · 2007-01-27, 16:38

Doing a quick check through the top 5000 site

42717*2^905792+1 is prime! L159 2005
44131*2^995972+1 is prime! SB3 2002 - very valuable "Seventeen or Bust", a first prime for 44131 and so this will save man years of work

Xentar · 2007-01-28, 21:52

Unreserving Base18 Sierpinski

k=122 tested till n=110746
no primes found - anyone else want to try?

381*18^24108+1 is a probable prime.
Do I have to register this prime somewhere? Prime Pages says, it is too small.

k=18 and k=324
stopped testing, because k = base

thommy · 2007-01-29, 07:37

Quote:

Originally Posted by Xentar

381*18^24108+1 is a probable prime.
Do I have to register this prime somewhere? Prime Pages says, it is too small.

Simply no.

robert44444uk · 2007-02-02, 04:16

Prof Caldwell has pointed out an error in the k value quoted for Base 12 Sierpinski, due to me choosing the wrong covering set to analyse.

In fact the covering set 5,13,29 produces a Sierpinski at k=521, and nominal sieving leaves 261,378 and 404 to find primes for, in addition to the GFN k's 12 and 144.

Recalculating gives the Riesel at 376, with the following unfound at n=5000

25,27,64,300,324 which are all highly composite (all 2,3, and 5), I will leave it to others to demonstrate that these factor (I am feeling lazy today)

robert44444uk · 2007-02-09, 04:37

I looked at the base 16 sierpinski for all k >60000, report as follows:

k n prime

60343 5745
60541 44085
60891 10036
61617 7845
61687 8948
62802 42004
63390 23511
63411 18016
64518 36998
65127 5206
65397 6222

No primes were found for the following k, tested up to the following n:

60070 53562
63405 42335
63853 39256
64620 75696
65077 58138
65623 64630

Will reserve all between k=50000 and k=60000

2007-01-27, 03:26	#111
robert44444uk Jun 2003 Oxford, UK 29·67 Posts	Base 16 Ok, here are the next few candidates for 16, all tested to n=4295. Last k tested was 47805 27592 27838 28593 28918 29445 30250 30397 31347 31912 32161 32350 32556 32673 33661 33771 34528 34543 35257 35320 35548 35818 35845 36735 37372 38440 38562 38776 39322 39337 39781 40000 40410 41530 42052 42376 42717 42745 43368 43398 43468 43485 44035 44131 44490 45306 45712 46471 46528 47176 47298 47395 47482 47616

2007-01-27, 10:50	#112
robert44444uk Jun 2003 Oxford, UK 3627₈ Posts	Base 16 Sierpinski And here is the last batch of Sierpinski 16, tested to n=5098 47818 48697 48772 48976 49386 49860 50166 50863 50865 51171 51427 52072 53226 53653 53941 54610 55306 55611 55846 55897 56866 57238 57795 57867 58582 58791 58855 59890 60070 60343 60541 60891 61617 61687 62802 63390 63405 63411 63853 64518 64620 65077 65127 65397 65536 square 65623 Last fiddled with by robert44444uk on 2007-01-27 at 10:58

2007-01-27, 12:05	#115
robert44444uk Jun 2003 Oxford, UK 797₁₆ Posts	Sierpinski 16 I will reserve those above k=60000 and take them quite high

2007-01-27, 16:38	#117
robert44444uk Jun 2003 Oxford, UK 29×67 Posts	Base 16 Sierpinski Doing a quick check through the top 5000 site 427172^905792+1 is prime! L159 2005 441312^995972+1 is prime! SB3 2002 - very valuable "Seventeen or Bust", a first prime for 44131 and so this will save man years of work

2007-01-28, 21:52	#118
Xentar Sep 2006 187₁₀ Posts	Base 18 Sierpinski Unreserving Base18 Sierpinski k=122 tested till n=110746 no primes found - anyone else want to try? 38118^24108+1 is a probable prime. Do I have to register this prime somewhere? Prime Pages says, it is too small. k=18 and k=324 stopped testing, because k = base Last fiddled with by Xentar on 2007-01-28 at 21:54*

2007-01-27, 11:01	#113
robert44444uk Jun 2003 Oxford, UK 3627₈ Posts	In post 112, k=40000 is square

2007-02-02, 04:16	#120
robert44444uk Jun 2003 Oxford, UK 29×67 Posts	Base 12 Sierpinski Prof Caldwell has pointed out an error in the k value quoted for Base 12 Sierpinski, due to me choosing the wrong covering set to analyse. In fact the covering set 5,13,29 produces a Sierpinski at k=521, and nominal sieving leaves 261,378 and 404 to find primes for, in addition to the GFN k's 12 and 144. Recalculating gives the Riesel at 376, with the following unfound at n=5000 25,27,64,300,324 which are all highly composite (all 2,3, and 5), I will leave it to others to demonstrate that these factor (I am feeling lazy today) Last fiddled with by robert44444uk on 2007-02-02 at 04:27

2007-02-09, 04:37	#121
robert44444uk Jun 2003 Oxford, UK 29×67 Posts	Base 16 Sierpinski I looked at the base 16 sierpinski for all k >60000, report as follows: k n prime 60343 5745 60541 44085 60891 10036 61617 7845 61687 8948 62802 42004 63390 23511 63411 18016 64518 36998 65127 5206 65397 6222 No primes were found for the following k, tested up to the following n: 60070 53562 63405 42335 63853 39256 64620 75696 65077 58138 65623 64630 Will reserve all between k=50000 and k=60000 Last fiddled with by robert44444uk on 2007-02-09 at 04:38

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