20130530, 21:09  #1 
"Nathan"
Jul 2008
Maryland, USA
5·223 Posts 
How close have you been to finding a Mersenne prime?
Define "close" in the following manner: a residue of 000000000001 is the closest possible residue to a Mersenne prime, while FFFFFFFFFFFF is the farthest possible residue from a Mersenne prime.
Given this definition, what is the closest/farthest you have personally been from discovering a new Mersenne prime? How about GIMPS as a whole? 
20130530, 21:52  #2 
"Vincent"
Apr 2010
Over the rainbow
B16_{16} Posts 
pretty bad for me
06738331905537__ 
20130530, 22:22  #3 
6809 > 6502
"""""""""""""""""""
Aug 2003
101×103 Posts
2^{2}×11×239 Posts 

20130530, 22:25  #4 
Account Deleted
"Tim Sorbera"
Aug 2006
San Antonio, TX USA
7·13·47 Posts 
Excluding knownbad residues, my "closest" in the last 365 days is 054A974FAF0241__ (the sorting at http://www.mersenne.org/results/ makes this easy to find).
I think the definition should be such that 000000000001 and FFFFFFFFFFFF are equally close  they're each just 1 apart from showing all zeroes in the 64bit residue. In other words: the "closest" residue is the one that is closest to 0 mod 2^64. If we drop the "Mersenne" restriction and I look at my PRPnet log files, my closest is: 0000083778FDEA40 on 507292*40^20317+1. I've run enough tests on even smaller numbers that I might have closer ones out there, but not in log files that are at hand (or exist at all). 
20130530, 22:33  #5 
"Vincent"
Apr 2010
Over the rainbow
2·3·11·43 Posts 
I Could see Chuck Curtis smugly posting 3 "000000000000" residue

20130530, 23:00  #6 
Mar 2006
Germany
2^{3}×3^{2}×41 Posts 
1881*2^7741261 is not prime. Res64: 00000F12ABCED83E
1745*2^8725061 is not prime. Res64: 00000E6B7FE01929 797*2^10888601 is not prime. Res64: 00000C48959C0818 1471*2^9445751 is not prime. Res64: 000008C5C489296D 333*2^11947941 is not prime. Res64: 0000085458B0E7B9 3645*2^21+1 is not prime. Proth RES64: 000000015B5CADFD 108045*2^18+1 is not prime. Proth RES64: 00000004206C33F6 651358155*2^13+1 is not prime. RES64: 0000000000081BF1 607815*2^17+1 is not prime. RES64: 00000000000002D9 and many other examples like these. 
20130530, 23:40  #7 
Aug 2006
3·1,993 Posts 
So many ways to measure distance!
Linearly, from 000...0 to FFF...F? Circularly, with FFF...F being just as near as 000...1? Digitwise, so 100...0 and 000...1 are equally far? By digits but circularly? Etc. 
20130530, 23:52  #8 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
7×23×61 Posts 
Code:
# pfgw f0 b2 q"2^65536+2^32768+1" 2^65536+2^32768+1 is composite: RES64: [0000000000000000] 
20130531, 00:04  #9 
Just call me Henry
"David"
Sep 2007
Liverpool (GMT/BST)
2^{5}·11·17 Posts 
0x2D9=729=3^6
This implies I believe(assuming that the residue being 2D9 wasn't a fluke)(607815*2^17+1)/(6+1) is 3PRP(In reality it is prime). There are probably more similar examples in your list. It would be nice if we could harness this to find prps. 
20130531, 00:12  #10 
If I May
"Chris Halsall"
Sep 2002
Barbados
2×3×1,741 Posts 
Code:
mysql> select Exponent.Exponent,Users.DisplayName,Assigned.FactFrom,Assigned.FactTo from Assigned,Exponent,Users where Assigned.Exponent=Exponent.Exponent and Exponent.Status=1 and Assigned.User=Users.User; +++++  Exponent  DisplayName  FactFrom  FactTo  +++++  57885161  Jerry Hallett  72  73  +++++ 1 row in set (0.00 sec) 
20130531, 00:37  #11 
If I May
"Chris Halsall"
Sep 2002
Barbados
24316_{8} Posts 
But, to be fair, it was close...
Code:
mysql> select Exponent.Exponent,Users.DisplayName,Assigned.FactFrom,Assigned.FactTo from Assigned,Exponent,Users where Assigned.Exponent=Exponent.Exponent and Exponent.Exponent>=57884571 and Exponent.Exponent<=57885257 and Assigned.User=Users.User and Assigned.WorkType=1; +++++  Exponent  DisplayName  FactFrom  FactTo  +++++  57884647  KyleAskine  72  73   57884747  Bdot  72  73   57884891  Jerry Hallett  72  73   57885143  Bdot  72  73   57885161  Jerry Hallett  72  73   57885167  Bdot  72  73   57885209  KyleAskine  72  73   57885211  KyleAskine  72  73   57885257  KyleAskine  72  73  +++++ 9 rows in set (0.01 sec) 
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