mersenneforum.org Changes to srsieve2
 Register FAQ Search Today's Posts Mark Forums Read

2020-08-02, 20:24   #12
gd_barnes

May 2007
Kansas; USA

7×17×89 Posts

Quote:
 Originally Posted by rogue Question. If k*b^n+c is not evenly divisible by d, should those terms removed prior to sieving?

Yes.

2020-08-04, 09:58   #13
henryzz
Just call me Henry

"David"
Sep 2007
Liverpool (GMT/BST)

174016 Posts

Quote:
 Originally Posted by gd_barnes Yes.
Maybe with a warning but yes. It may be deliberate it may be due to a mistake.

2020-08-04, 12:09   #14
rogue

"Mark"
Apr 2003
Between here and the

32·52·29 Posts

Quote:
 Originally Posted by henryzz Maybe with a warning but yes. It may be deliberate it may be due to a mistake.
Are you thinking that srsieve2 could output a message like "xxx terms for sequence k*b^n+c are not divisible by d and have been removed"?

2020-08-04, 13:52   #15
henryzz
Just call me Henry

"David"
Sep 2007
Liverpool (GMT/BST)

26×3×31 Posts

Quote:
 Originally Posted by rogue Are you thinking that srsieve2 could output a message like "xxx terms for sequence k*b^n+c are not divisible by d and have been removed"?
Yes that could make sense.

Last fiddled with by henryzz on 2020-08-04 at 15:08

 2020-08-04, 19:36 #16 gd_barnes     May 2007 Kansas; USA 7×17×89 Posts Agreed
 2020-10-22, 07:52 #17 sweety439     "99(4^34019)99 palind" Nov 2016 (P^81993)SZ base 36 7×457 Posts Is srsieve2 updated? If so, can you use it to reserve the S3 problem in Sierpinski conjectures and proofs and the R43 problem in Riesel conjectures and proofs? (the latter is a 1k base and I have already used PARI to search it to 12K with no (probable) prime found)
 2020-10-22, 12:14 #18 rogue     "Mark" Apr 2003 Between here and the 145758 Posts I have not made the change. Too busy.
2020-11-01, 00:25   #19
sweety439

"99(4^34019)99 palind"
Nov 2016
(P^81993)SZ base 36

7·457 Posts

Quote:
 Originally Posted by rogue I have not made the change. Too busy.
See the edit https://github.com/curtisbright/mepn...914128b3303960 in GitHub, you can just remove srsieve divisible by 2 check.

 2020-11-01, 00:36 #20 sweety439     "99(4^34019)99 palind" Nov 2016 (P^81993)SZ base 36 1100011111112 Posts By the way, this removing is original used for solving the "minimal prime problem" for odd bases, in 2015, a mega-digit (probable) prime (106*23^800873-7)/11 (which is 9{E_800873} in base 23, and the largest minimal prime in base 23) was found to solve the "minimal prime problem" in base 23 (see PRP top link), if one allows probable primes in place of proven primes. The "minimal prime problem" is solved only for bases 2~16, 18, 20, 22~24, 30, 42, bases <=30 are still reserving (see https://github.com/curtisbright/mepn...ee/master/data, like the CRUS reserving for unproven Sierpinski/Riesel problems) and currently at width 200K and above, but bases 31~50 (see https://github.com/RaymondDevillers/primes) are currently only at width 10K, you can also reserve them like the CRUS reserving. Note: There are some minimal prime for base 31~50 with width > 10K found by CRUS: Base 37: (families FY{a} and R8{a} can be removed) 590*37^22021-1 (= FY{a_22021}) 1008*37^20895-1 (= R8{a_20895}) Base 45: (families O{0}1 and AO{0}1 can be removed, and hence families O{0}1F1, O{0}ZZ1, unless they have small (probable) prime) 24*45^18522+1 (= O{0_18521}1) 474*45^44791+1 (= AO{0_44790}1) [this prime is not minimal prime] Base 49: (families 11c{0}1, Fd{0}1, SL{m} and Yd{m} can be removed, and hence families S6L{m}, YUUd{m}, YUd{m}, unless they have small (probable) prime) 2488*49^29737+1 (= 11c{0_29736}1) 774*49^18341+1 (= Fd{0_18340}1) 1394*49^52698-1 (= SL{m_52698}) 1706*49^16337-1 (= Yd{m_16337}) Also, I have found a minimal prime with width > 10K in base 40: (13998*40^12381+29)/13, which equals Qa{U_12380}X in base 40 (the only other unsolved family in base 40 (S{Q}d (86*40^n+37)/3) was tested by me to width 87437, no (probable) prime found Last fiddled with by sweety439 on 2020-11-01 at 00:38
2021-06-11, 16:26   #21
sweety439

"99(4^34019)99 palind"
Nov 2016
(P^81993)SZ base 36

7×457 Posts

Did srsieve2 update?

I want to solve the minimal prime problem for bases 2<=b<=50. Can srsieve2 handle (a*b^n+c)/d for d>1 now? For odd bases b, srsieve2 cannot be used to sieve a*b^n+c, as it will return "error: all numbers are divisible by 2".

These files are the algebra form for the unsolved families for bases 29, 31, 33, 35, 37 (when searched to 10K digits).
Attached Files
 unsolved29algebra.txt (863 Bytes, 57 views) unsolved31algebra.txt (441 Bytes, 56 views) unsolved33algebra.txt (691 Bytes, 56 views) unsolved35algebra.txt (317 Bytes, 58 views) unsolved37algebra.txt (5.5 KB, 53 views)

Last fiddled with by sweety439 on 2021-06-11 at 16:38

2021-06-11, 16:41   #22
sweety439

"99(4^34019)99 palind"
Nov 2016
(P^81993)SZ base 36

7×457 Posts

To make you understand, these are the base b form for these unsolved families (12{3}45 means 12333...33345, i.e. {1245, 12345, 123345, 1233345, 12333345, 123333345, ...}, and A-Z means digit value 10-35, a-z means digit value 36-61) for bases 29, 31, 33, 35, 37

Families are sorted alphabetize, "{" is after "z"
Attached Files
 unsolved29.txt (346 Bytes, 56 views) unsolved31.txt (171 Bytes, 53 views) unsolved33.txt (252 Bytes, 52 views) unsolved35.txt (120 Bytes, 55 views) unsolved37.txt (2.1 KB, 52 views)

Last fiddled with by sweety439 on 2021-06-11 at 16:44

All times are UTC. The time now is 10:41.

Wed Jan 19 10:41:09 UTC 2022 up 180 days, 5:10, 0 users, load averages: 2.11, 1.77, 1.57