mersenneforum.org  

Go Back   mersenneforum.org > Prime Search Projects > Conjectures 'R Us

Closed Thread
 
Thread Tools
Old 2007-01-07, 20:17   #45
michaf
 
michaf's Avatar
 
Jan 2005

47910 Posts
Default

2 more down:

2529*22^3700-1 is prime
5751*22^4272+1 is prime
michaf is offline  
Old 2007-01-07, 20:54   #46
rogue
 
rogue's Avatar
 
"Mark"
Apr 2003
Between here and the

2·3,001 Posts
Default

These base 10 candidates are all prime
2311*10^1000+1
2607*10^780+1
2683*10^1049+1
3301*10^1228+1
3312*10^960+1
3345*10^584+1
3981*10^1239+1
4863*10^1554+1
5125*10^1597+1
5556*10^1412+1
6841*10^771+1
7459*10^978+1
7534*10^1377+1
7866*10^1854+1
8454*10^1064+1
8724*10^996+1
8922*10^1020+1
9043*10^1342+1
1506*10^872-1
3015*10^1127-1
4577*10^1145-1
5499*10^544-1
5897*10^1159-1
6633*10^1753-1
7602*10^555-1
8174*10^753-1
9461*10^579-1
rogue is offline  
Old 2007-01-07, 20:58   #47
tnerual
 
tnerual's Avatar
 
Oct 2006

7×37 Posts
Default

looking at all messages above, here are the actual work to do ... with reservation (limited)

it includes all confirmed observation:

base 10 maybe screwed at the end (see post 49 or 50 from citrix and the possible bug in srsieve)

Code:
Base 6:

Sierpinski 
1 to 243417
Reisel
1 to 213409

Base 7:

Totally horrible. Possible covering set with repeat every 24 n is [19,5,43,1201,13,181,193,73], also 5 other sets perming 73, 193 and 409.

Sierpinski and Riesel numbers are both lower than 162643669672445

Work is needed to find a low k value which is Riesel or Sierpinski.

Base 8:

Sierpinski
1
Riesel (done?)

Base 9:

Sierpinski (done ?)
Riesel
4 jasong 
16
36
64 
Note 16 and 64 are subsets of 4.

Base 10:

Sierpinski
804*10^n+1
1024*10^n+1
2157*10^n+1
2661*10^n+1
4069*10^n+1
5028*10^n+1
5512*10^n+1
5565*10^n+1
6172*10^n+1
7404*10^n+1
7666*10^n+1
7809*10^n+1
8194*10^n+1
8425*10^n+1
8667*10^n+1
8889*10^n+1
9021*10^n+1
9175*10^n+1
Riesel
1343*10^n-1
1803*10^n-1
1935*10^n-1
2276*10^n-1
2333*10^n-1
3356*10^n-1
4016*10^n-1
4421*10^n-1
4478*10^n-1
6588*10^n-1
6665*10^n-1
7019*10^n-1
8579*10^n-1
9701*10^n-1
9824*10^n-1
10176*10^n-1

Base 11:

Sierpinski
416 tnerual
958 tnerual
Riesel
62
682
862
904
1528
2410
2690
3110
3544
3788
4208
4564

Base 12:

Sierpinski
1 to 14599
Riesel
1 to 16328.

Base 13:

Sierpinski (done) 
Riesel
288

Base 14: done

Base 15:

Horrible. A covering set is [241,113,211,17,1489,13,3877], and Sierpinski and Riesel values are therefore less than 7330957703181619. As bad as the base 3 problem.

Base 16:

Sierpinski number not known,
186 (to be removed see post #49 below by citrix)
2158 (tested up to n=4000 by citrix)
2857 (tested up to n=4000 by citrix)
2908 (tested up to n=4000 by citrix)
3061 (tested up to n=4000 by citrix)
4885 (tested up to n=4000 by citrix)
5886 (tested up to n=4000 by citrix)
6348 (tested up to n=4000 by citrix)
6663 (tested up to n=4000 by citrix)
6712 (tested up to n=4000 by citrix)
7212 (tested up to n=4000 by citrix)
7258 (tested up to n=4000 by citrix)
7615 (tested up to n=4000 by citrix)
7651 (tested up to n=4000 by citrix)
7773 (tested up to n=4000 by citrix)
8025 (tested up to n=4000 by citrix)
10001 to 66740
Riesel
1343*16^n-1
1803*16^n-1
1935*16^n-1
2333*16^n-1
3015*16^n-1
3332*16^n-1
4478*16^n-1
4500*16^n-1
4577*16^n-1
5499*16^n-1
5897*16^n-1
6588*16^n-1
6633*16^n-1
6665*16^n-1
7019*16^n-1
7602*16^n-1
8174*16^n-1
8579*16^n-1
10001 to 33965

Base 17:

Sierpinski 
92 (LTD)
160 (LTD)
244 (LTD)
262 (LTD)
Riesel (done)


Base 18:

Sierpinski
18 xentar
324 xentar
122 xentar
381 xentar
Riesel (done)

Base 19:
?

Base 20: 
?

Base 21:

Sierpinski 
118 (checked to n=3500)
riesel (done)

Base 22:

Sierpinski
22
484
942
1611
1908
2991
4233
5061
5128
5659
6234
6462
Riesel
185
1013
1335
2853
3104
3426
3656
4001
4070
4118
4302
4440

Last fiddled with by tnerual on 2007-01-07 at 21:56 Reason: with info up to post 50
tnerual is offline  
Old 2007-01-07, 21:06   #48
rogue
 
rogue's Avatar
 
"Mark"
Apr 2003
Between here and the

2×3,001 Posts
Default

I think there is a bug in srsieve (although it could be the version I have). When I input all of the base 10 candidates, it immediately removes 9701*10^n-1, but if I sieve that separately or change my input list, it is not removed. Very odd.
rogue is offline  
Old 2007-01-07, 21:24   #49
Citrix
 
Citrix's Avatar
 
Jun 2003

32·52·7 Posts
Default

@ rouge, I have checked base 10 upto 2100. Here are the candidates left.

804*10^n+1
1024*10^n+1
2157*10^n+1
2661*10^n+1
4069*10^n+1
5028*10^n+1
5512*10^n+1
5565*10^n+1
6172*10^n+1
7404*10^n+1
7666*10^n+1
7809*10^n+1
8194*10^n+1
8425*10^n+1
8667*10^n+1
8889*10^n+1
9021*10^n+1
9175*10^n+1
1343*10^n-1
1803*10^n-1
1935*10^n-1
2276*10^n-1
2333*10^n-1
3356*10^n-1
4016*10^n-1
4421*10^n-1
4478*10^n-1
6588*10^n-1
6665*10^n-1
7019*10^n-1
8579*10^n-1
9461*10^n-1

Here are some primes I found.
8922*10^504+1
8454*10^509+1
3312*10^544+1
5499*10^544+-1
7602*10^555+-1
3345*10^584+1
8174*10^753+-1
6841*10^771+1
2607*10^780+1
3301*10^788+1
3345*10^866+1
1506*10^872+-1
8724*10^924+1
3312*10^960+1
7459*10^978+1
8724*10^996+1
2311*10^1000+1
8922*10^1020+1
9043*10^1034+1
6633*10^1036+-1
2683*10^1049+1
8454*10^1064+1
7459*10^978+1
3015*10^1127+-1
4577*10^1145+-1
5897*10^1159+-1
3981*10^1239+1
7534*10^1377+1
5556*10^1412+1
4863*10^1554+1
5125*10^1597+1
7866*10^1854+1
3332*10^1952+-1
2111*10^1960+-1
8953*10^2057+1
6687*10^2097+1

The last few candidates are missing. Once srsieve removed 9701 from the sieve I assumed it was sierpinski and removed the ones after that from the sieve. same on the riesel side.

You can continue on base 10. I will not work on it.

Also for base 16. looking on prothsearch.net 93*2^586453+1 is prime. This removes 186.
On riesel side 225*2^9005-1 is prime. So 450 is removed.

Last fiddled with by Citrix on 2007-01-07 at 21:41
Citrix is offline  
Old 2007-01-07, 21:54   #50
tnerual
 
tnerual's Avatar
 
Oct 2006

10316 Posts
Default

is there any application where i can enter the base (fixed), a range of k and then a starting n. then start the app.

the app must remove (and log) all prime k for n then test all remaining k for primality at the next n and so on.

i'm sure there is something like that but i don't know what.

citrix i think you use that (looking at your 10000 k range on base 16, you can't do it manually )
tnerual is offline  
Old 2007-01-07, 22:09   #51
Citrix
 
Citrix's Avatar
 
Jun 2003

62716 Posts
Default

Quote:
Originally Posted by tnerual View Post

citrix i think you use that (looking at your 10000 k range on base 16, you can't do it manually )
I wrote a program for myself for the low n's. Then I used srsieve and PFGW for high n and removed candidates manually.
Citrix is offline  
Old 2007-01-08, 03:27   #52
rogue
 
rogue's Avatar
 
"Mark"
Apr 2003
Between here and the

177216 Posts
Default

Here are more base 10 primes:

2276*10^2726-1
2333*10^2113-1
4016*10^3647-1
4478*10^4817-1
6588*10^7442-1
9701*10^6538-1
9824*10^1857-1
1024*10^4554+1
2157*10^3560+1
2661*10^2681+1
5512*10^3004+1
5565*10^3175+1
804*10^7558+1
8425*10^3661+1
8667*10^6617+1
8889*10^7588+1
9021*10^8090+1

The remaining in base 10 are:

4069*10^n+1
5028*10^n+1
6172*10^n+1
7404*10^n+1
7666*10^n+1
7809*10^n+1
8194*10^n+1

1343*10^n-1
1803*10^n-1
1935*10^n-1
3356*10^n-1
4421*10^n-1
6665*10^n-1
7019*10^n-1
8579*10^n-1

I'll continue on these for a while.

Last fiddled with by rogue on 2007-01-08 at 03:31
rogue is offline  
Old 2007-01-08, 06:37   #53
robert44444uk
 
robert44444uk's Avatar
 
Jun 2003
Oxford, UK

190310 Posts
Default

Quote:
Originally Posted by michaf View Post
Without any math skills... so excuse me if I bugger here :>

base 22:

22*22^n + 1
=
22^(n+1) + 1
=
1*22^(n+1) + 1

so, k = 1
and that one is eliminated, therefore is k=22 and 484?
Unfortunately not. 1*22^1+1=23 prime, but, I think we decided for the Sierpinski base 5 exercise, that we would not use n=0, otherwise k=22 could be eliminated but not 484.
robert44444uk is offline  
Old 2007-01-08, 06:39   #54
robert44444uk
 
robert44444uk's Avatar
 
Jun 2003
Oxford, UK

11·173 Posts
Default Base 16

Quote:
Originally Posted by Citrix View Post
Also for base 16. looking on prothsearch.net 93*2^586453+1 is prime. This removes 186.
On riesel side 225*2^9005-1 is prime. So 450 is removed.
Brilliant, it is worth checking the top 5000 and prothsearch from time to time!

Last fiddled with by robert44444uk on 2007-01-08 at 06:49
robert44444uk is offline  
Old 2007-01-08, 06:47   #55
robert44444uk
 
robert44444uk's Avatar
 
Jun 2003
Oxford, UK

11×173 Posts
Default Base 11

Quote:
Originally Posted by tnerual View Post
what do you think of 416*11^n-1 in 5 seconds i can find all factors for n=1 to n=50000000 maybe it's a lowest riesel ...

if it is i'm lucky/stupid (confusion between -1 and +1 with 416 one of the two last k in sierpinski side)

LAurent
Unfortunately it is a trivial case, all n are divisible by 5.
robert44444uk is offline  
Closed Thread

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Very Prime Riesel and Sierpinski k robert44444uk Open Projects 587 2016-11-13 15:26
Riesel/Sierp #'s for bases 3, 7, and 15 Siemelink Conjectures 'R Us 105 2009-09-04 06:40
Sierpinski/Riesel Base 10 rogue Conjectures 'R Us 11 2007-12-17 05:08
Sierpinski / Riesel - Base 23 michaf Conjectures 'R Us 2 2007-12-17 05:04
Sierpinski / Riesel - Base 22 michaf Conjectures 'R Us 49 2007-12-17 05:03

All times are UTC. The time now is 09:10.

Wed Nov 25 09:10:54 UTC 2020 up 76 days, 6:21, 4 users, load averages: 1.86, 1.61, 1.39

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.

This forum has received and complied with 0 (zero) government requests for information.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation.
A copy of the license is included in the FAQ.