mersenneforum.org Predict M47
 Register FAQ Search Today's Posts Mark Forums Read

2008-09-16, 19:18   #23
T.Rex

Feb 2004
France

11100101002 Posts

Quote:
 Originally Posted by nngs I assume $\log_2(\log_2(M_{\rm n}))$ depends on n as $A+B\times n+C\sin(D\times n+E)$ The best fit using all 46 known mersenne primes is: A=1.1253235 +/- 0.125 B=0.55185022 +/- 0.00484 C=0.68753629 +/- 0.0850 D=0.29490442 +/- 0.00560 E=-3.2489748 +/- 0.149
Interesting. How did you find A, B, C, D and E ?

The theoretical (but not yet proved !) Poisson's slope is : $1/e^\gamma= 0.5614594...$
So, your B is not so far.

Tony

2008-09-16, 20:19   #24
nngs

Jun 2004

22×3×5 Posts

Quote:
 Originally Posted by T.Rex Interesting. How did you find A, B, C, D and E ? The theoretical (but not yet proved !) Poisson's slope is : $1/e^\gamma= 0.5614594...$ So, your B is not so far. Tony
I use a IDL route called LMFIT. Here is the first sentence in LMFIT help:

Quote:
 The LMFIT function does a non-linear least squares fit to a function with an arbitrary number of parameters.
If I use A+B*n only (which will give me B=0.561...), the residuals show a sinusoidal pattern. So I add a sine term in my guess function.

 2008-09-16, 22:49 #25 petrw1 1976 Toyota Corona years forever!     "Wayne" Nov 2006 Saskatchewan, Canada 2×2,341 Posts Well, breaking from the mathematically sound 2^n intervals, I charted the number of MPs by 10^n digits: 0 = 7 (for 10^0 digits there are 7 MPs) 1 = 5 2 = 6 3 = 8 4 = 5 5 = 6 6 = 7 7 = 2 (so far) Again, based on unsound principles, excluding the first interval, I see a pattern (5,6,8,5,6,'7'). So, it would suggest there is one more MP at 10^6 digits. But with all the focus on larger ranges it could be a while before that range clears so I am guessing it will be in the 29M range but not found until November 2009.
 2008-09-17, 05:56 #26 Primeinator     "Kyle" Feb 2005 Somewhere near M52.. 3×5×61 Posts I predict M47's exponent will be approximately 47,300,000 and will be discovered in October of next year.
 2008-09-17, 17:59 #27 Uncwilly 6809 > 6502     """"""""""""""""""" Aug 2003 101×103 Posts 5×19×103 Posts I have started tabulating the data. I am up to date at this point.
 2008-09-17, 18:49 #28 R. Gerbicz     "Robert Gerbicz" Oct 2005 Hungary 33×5×11 Posts Never. There is no more Mersenne prime, the list is complete.
2008-09-17, 19:12   #29

Aug 2008

2·43 Posts

Quote:
 Originally Posted by Uncwilly I have started tabulating the data. I am up to date at this point.
Once we get a few more, we could make a chart, and send it to mini-geek, so that he can update his post.

"All mersenne primes have been found" is a valid guess, so there should be a bucket for that. In fact, I would say that as of right now, Gerbicz is currently the leading contender in this contest

2008-09-17, 19:25   #30
Mini-Geek
Account Deleted

"Tim Sorbera"
Aug 2006
San Antonio, TX USA

17×251 Posts

Quote:
 Originally Posted by uigrad ... and send it to mini-geek, so that he can update his post.
Only mods can edit posts after 1 hour, so someone else will have to put it up on the first post, if a chart is made (I think that's a good idea).

 2008-09-17, 19:28 #31 petrw1 1976 Toyota Corona years forever!     "Wayne" Nov 2006 Saskatchewan, Canada 2×2,341 Posts To the contrary could there be MORE than expected? I started monitoring the "pretty colorful stats report" almost 3 years ago (Oct 25, 2005). At the time there were 42 known primes and 2.64 "Expected New Primes" for an expected total between 44 and 45. Not quite 3 years later we are at 46 known primes and it still reports 1.77 expected for an expected total NOW closer to 48 ... 3 more than expected 3 years ago. Is this not mathematically significant enough to make one wonder if they are LESS rare than we thought?
2008-09-17, 19:50   #32
philmoore

"Phil"
Sep 2002
Tracktown, U.S.A.

111910 Posts

Quote:
 Originally Posted by petrw1 Is this not mathematically significant enough to make one wonder if they are LESS rare than we thought?
Take a look at Chris Caldwell's updated graph at:
http://primes.utm.edu/mersenne/heuristic.html
Note the last seven points - definitely a significantly tighter clustering than the clusterings at M21 through M23 and M24 through M26. Could be one of the following:

1) Purely a statistical deviation.
2) The beginning of a departure from the heuristic which has been pretty successful so far in characterizing the overall distribution of Mersenne primes.
3) Just the universe's way of encouraging us to continue searching for more Mersenne primes!

2008-09-17, 20:14   #33
Primeinator

"Kyle"
Feb 2005
Somewhere near M52..

3·5·61 Posts

Quote:
 2) The beginning of a departure from the heuristic which has been pretty successful so far in characterizing the overall distribution of Mersenne primes.
I'm hoping it is possibility number two.

 Similar Threads Thread Thread Starter Forum Replies Last Post Uncwilly Lounge 65 2018-01-06 17:11 Raman Lounge 3 2016-10-03 19:23 Xyzzy Lounge 66 2014-02-01 14:45 ewmayer Lounge 215 2008-09-17 21:14 Uncwilly Lounge 22 2005-02-27 02:11

All times are UTC. The time now is 17:27.

Sat Jul 24 17:27:37 UTC 2021 up 1 day, 11:56, 1 user, load averages: 2.00, 1.80, 1.84