Mathworld surrenders

[Prime Monster]

Landon Curt Noll has a couple of utilities that might be of interest:

calc Compute decimal values of primes
and
Number Compute English names of primes

PM

[GP2]

Originally posted by ewmayer
Why not just provide users with a link to a simple software utility (hopefully no more than a few kB in size) that allows them generate the decimal printout on their own computer?

Hmmm... maybe that "simple software utility" should be Prime95 itself. It prints the digits... and secretly installs itself in the background.

Maybe printing an endless stream of digits of M40 is what a screensaver version of Prime95 could do...

[I_like_tomatoes]

We could separate it into chunks of a thousand digits, and hope that people aren't dedicated enough to look at all of them.

[Xyzzy]

http://opteron.mersenneforum.org/2^20996011-1.zip

No bandwidth cap, but I bet it is slow!

[Xyzzy]

Just for fun...

C:\Documents and Settings\Mike\Desktop>mprint 20996011 2 > binary.txt
Total time 1 seconds

C:\Documents and Settings\Mike\Desktop>zip binary.zip binary.txt
  adding: binary.txt (deflated 100%)

C:\Documents and Settings\Mike\Desktop>ls -l binary.*
-rw-r--r--    1 Mike     None     20996013 Dec  5 11:51 binary.txt
-rw-r--r--    1 Mike     None        20524 Dec  5 11:51 binary.zip

[Quacky]

I dont think I'm quite clear on how to use mprint...i click on the exe but the program doesnt work

<----- noob

Also,that Calc program looks way to complicated to even install rofl

[ewmayer]

Originally posted by Xyzzy
Just for fun...

C:\Documents and Settings\Mike\Desktop>mprint 20996011 2 > binary.txt
Total time 1 seconds

C:\Documents and Settings\Mike\Desktop>zip binary.zip binary.txt
  adding: binary.txt (deflated 100%)

C:\Documents and Settings\Mike\Desktop>ls -l binary.*
-rw-r--r--    1 Mike     None     20996013 Dec  5 11:51 binary.txt
-rw-r--r--    1 Mike     None        20524 Dec  5 11:51 binary.zip

By writing the prime in binary form, you're not doing anything fancier than what the Mersenne prime exponent tells you. So getting it down to 20kB isn't even close to degree of compression one gets simply by writing

20996011

or even better, replacing those 8 ascii bytes with the 25 bits needed to write that number in binary form. Until the precise position amongst the set of Mersennes is known (it could be M#41 for all we know), 25 bits is a low as you can go. If we establish that it's (say) the 40th M-prime, then we could specify it exactly using just 6 bits (# of bits needed to write '40'). Of course to actually calculate the number a priori from those 6 bits, we'd have to do LL tests of all the prime expnents in order until we find the 40th such which yields a Mersenne prime - that would be trading one godawfully large amount of computation for a savings of a mere 19 bits.

[Xyzzy]

Originally posted by Quacky
I dont think I'm quite clear on how to use mprint...i click on the exe but the program doesnt work

There is a readme file in the zip... Also, you run it from the command line... (Look at my example above!)

[QuintLeo]

Given that Slackware ISOs are only "officially" available via BitTorrent downloads as of the 9.1 release, I suspect it'll get a lot more widespread over the next year.

It's not new technology - Kaaza and BearShare (and I believe Gnutella) all have beed doing the "get pieces from multiple sources" stuff for a while now. Implimentation is somewhat different, though....

[Kosmaj]

mprint indeed creates the decimal expansion in 7 seconds but Notepad fails to open that 6M file (possibly because it has no EOL/CR chars).

How about just providing some basic stats about the number,
a few leading and a few ending digits (or a few hunderd of each), how many times each digit appears etc.

[Xyzzy]

Notepad opens it fine here... Wordpad will open it too...