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I'm not trying to be inflammatory here... this is a genuine question.

However--most certainly--not a genuinely original question with any semblance of clue. How genuine can a question be if the person responding wonders if you've even heard of Archimedes?

Short answer: researchers pursue the limits of the computational arts in the same way that athletes pursue the limits of human performance (and continue to do so, long after breaking the 4 minute mile, and What good is that? I ask you with barely a hint of rhetorical flourish, having as much taste for shapely buns as anyone else).

Long ago in my first semester of what should have been a CS degree (the registrar's office bumped me into Science because too many instructors from their CS program had been poached the previous summer by IBM) on my own Z80 based system, I computed 2^44497-1 in binary (lordy, lordy) and then printed it out in decimal on a dot matrix printer with a very small numeric font such that it almost exactly covered one standard page. The formatted print in this case was harder than the compute. It was really just an exercise in gaining proficiency with the C language. My C compiler arrived in a zip-locked bag. Meanwhile, big CS U was force-feeding all their COOP students Fortran, COBOL, and Pascal--if you were lucky. Over in the Arts department, first or second year English Literature students were forcibly conscripted into introductory SNOBOL or PL/1 courses. I had a nice sideline going for one term assisting damsels in distress. C was considered harmful, so I had to learn it furtively by not showing up for class.

Decimal digits American style

It has remained my favorite five digit number ever since. Of course I didn't bother formatting the commas.

Actually, thinking way way way back, I don't I did memset a big block of memory with 0xFF and then call print(). I probably worked the problem in base 10,000 iteratively multiplying by 2^13 for 3500 odd passes.

Amazing where a small little problem like this might take you.

This

I prefer this one: http://www.isthe.com/chongo/tech/comp/calc/ No gui. Scriptable, with a c-style language. Very usefull.

I am a huge fan of Landon Curt Noll's calc program (known as "apcalc" in Debian/Ubuntu), and it's usually one of the very first things I install on my machine. It's CLI-only, and having it available to my via SSH means that I have a great calculator available to me anytime via my mobile phone. I don't care for RPN; calc lets me write an expression just like how I would on paper, so it is very intuitive. It has a large scientific library, too.

When I need to graph, I use gnuplot.

http://prime.isthe.com/no.index/chongo/merdigit/long-m42643801/prime-c.html

Before: 140 MB used
Several minutes and 1 maxed CPU core later: Jumping between 250 MB and 300 MB used before I gave up and closed the tab.

There is a link in TFA to the number. It gives an abbreviated version first, but links to the full number as well:

http://prime.isthe.com/chongo/tech/math/prime/m42643801/prime-c.html

• Digits of 2^42643801 - 1 with dot separators (instead of commas)
• English name of 2^42643801 - 1 using the American system
• English name of 2^42643801 - 1 using the European system
• English name of 2^42643801 - 1 using the American system with dashes
• English name of 2^42643801 - 1 using the European system with dashes

The dashed form of the English name is available at assist those who might actually want to read all or part of the +324 Megabyte name. :-)

• Digits of 2^42643801 - 1 with dot separators (instead of commas)
• English name of 2^42643801 - 1 using the American system
• English name of 2^42643801 - 1 using the European system
• English name of 2^42643801 - 1 using the American system with dashes
• English name of 2^42643801 - 1 using the European system with dashes

The dashed form of the English name is available at assist those who might actually want to read all or part of the +324 Megabyte name. :-)

• Digits of 2^42643801 - 1 with dot separators (instead of commas)
• English name of 2^42643801 - 1 using the American system
• English name of 2^42643801 - 1 using the European system
• English name of 2^42643801 - 1 using the American system with dashes
• English name of 2^42643801 - 1 using the European system with dashes

The dashed form of the English name is available at assist those who might actually want to read all or part of the +324 Megabyte name. :-)

• Digits of 2^42643801 - 1 with dot separators (instead of commas)
• English name of 2^42643801 - 1 using the American system
• English name of 2^42643801 - 1 using the European system
• English name of 2^42643801 - 1 using the American system with dashes
• English name of 2^42643801 - 1 using the European system with dashes

The dashed form of the English name is available at assist those who might actually want to read all or part of the +324 Megabyte name. :-)

• Digits of 2^42643801 - 1 with dot separators (instead of commas)
• English name of 2^42643801 - 1 using the American system
• English name of 2^42643801 - 1 using the European system
• English name of 2^42643801 - 1 using the American system with dashes
• English name of 2^42643801 - 1 using the European system with dashes

The dashed form of the English name is available at assist those who might actually want to read all or part of the +324 Megabyte name. :-)

• Digits of 2^42643801 - 1 with dot separators (instead of commas)
• English name of 2^42643801 - 1 using the American system
• English name of 2^42643801 - 1 using the European system
• English name of 2^42643801 - 1 using the American system with dashes
• English name of 2^42643801 - 1 using the European system with dashes

The dashed form of the English name is available at assist those who might actually want to read all or part of the +324 Megabyte name. :-)

• Digits of 2^42643801 - 1 with dot separators (instead of commas)
• English name of 2^42643801 - 1 using the American system
• English name of 2^42643801 - 1 using the European system
• English name of 2^42643801 - 1 using the American system with dashes
• English name of 2^42643801 - 1 using the European system with dashes

The dashed form of the English name is available at assist those who might actually want to read all or part of the +324 Megabyte name. :-)

Nope, we can already represent numbers as high as we want in words.

View it here in it's 12mb text form!!!!!!!!

Our initial attempt to solve this was to complain to the ISP of the referrer spammers. That did no good. The ISP was willing to listen, but not to act.

We did manage to actually track down the jerks who were doing the referrer spam. They told us that they were attempting to create links back to their sites for better search engine placement.

Our work-a-round was two fold. For various reasons we wanted to keep these our webalizer stats externally accessible. So we requested bots (the ones that follow the rules at least) to not index our external stats and we modified webalizer to not form links back to the referrers.

We edited our robots.txt file to exclude legit bots from our stats:

User-agent: *
Disallow: /stats

We also patched webalizer v2.01-10 to no longer form URLs to referrers. Now only a plain text line without the leading http:// shows up in the table. The original referrer spammers gave up when they lost off the the links back to their sites.

The bottom of the 0.basic.patch prevents webalizer from forming links back to referrers. See README-FIRST for details on this patch set.

Our initial attempt to solve this was to complain to the ISP of the referrer spammers. That did no good. The ISP was willing to listen, but not to act.

We did manage to actually track down the jerks who were doing the referrer spam. They told us that they were attempting to create links back to their sites for better search engine placement.

Our work-a-round was two fold. For various reasons we wanted to keep these our webalizer stats externally accessible. So we requested bots (the ones that follow the rules at least) to not index our external stats and we modified webalizer to not form links back to the referrers.

We edited our robots.txt file to exclude legit bots from our stats:

User-agent: *
Disallow: /stats

We also patched webalizer v2.01-10 to no longer form URLs to referrers. Now only a plain text line without the leading http:// shows up in the table. The original referrer spammers gave up when they lost off the the links back to their sites.

The bottom of the 0.basic.patch prevents webalizer from forming links back to referrers. See README-FIRST for details on this patch set.

Definition

Obfuscate: tr.v. -cated, -cating, -cates. 1. a. To render obscure. b. To darken. 2. To confuse: his emotions obfuscated his judgment. [LLat. obfuscare, to darken : ob(intensive) + Lat. fuscare, to darken < fuscus, dark.] -obfuscation n. obfuscatory adj.

Goals:

• To write the most Obscure/Obfuscated C program under the content rules.
• To show the importance of programming style, in an ironic way.
• To stress C compilers with unusual code.
• To illustrate some of the subtleties of the C language.
• To provide a safe forum for poor C code. :-)

And here is one entry from the IOCCC FAQ that talks about how the IOCCC got started:

One day (23 March 1984 to be exact), back Larry Bassel and I (

Landon Curt Noll) were working for National Semiconductor's Genix porting group, we were both in our offices trying to fix some very broken code. Larry had been trying to fix a bug in the classic Bourne shell (C code #defined to death to sort of look like Algol) and I had been working on the finger program from early BSD (a bug ridden finger implementation to be sure). We happened to both wander (at the same time) out to the hallway in Building 7C to clear our heads.

We began to compare notes: ''You won't believe the code I am trying to fix''. And: ''Well you cannot imagine the brain damage level of the code I'm trying to fix''. As well as: ''It more than bad code, the author really had to try to make it this bad!''.

After a few minutes we wandered back into my office where I posted a flame to net.lang.c inviting people to try and out obfuscate the UN*X source code we had just been working on.

BTW: I (Landon Curt Noll) had to post this

typo correction. Thus began the tradition of putting typos in the contest rules and guidelines ... to make them more obfuscated of course! :-)

BTW: This posting was made back in the days when AT&T was the evil giant. Now, Microsoft makes AT&T look mild and kind in comparison. :-( (IMHO) ).

BTW: See the story about the '' Bill Gates'' award. :-)

OK, back to the story. We (Larry and I) received a number of entries by EMail. When we began to receive messages from outside of the US, Larry and I decided to include International in the name. The 1st IOCCC winners were posted on 17 April 1984.

There were 4 winners in 1984:

<dis>honorable mention

One ironic twist is that LavaRnd used only the PWC (open source) module. We did NOT use the PWCX (binary-only) module. Our hotplug script did an rmmod of the pwcx module. We discovered that the PWCX module reduced the entropy that the webcams provided. The PWCX module, when loaded, made webcams a poorer entropy source.

LavaRnd used the entropy provided by the actual hardware. Our analysis showed that PWCX was in effect "faking" the larger image sizes by taking, say the true 160x120 pixel CCD output and expanding it to something like 640x480. The expansion was as if a 2D smoothing function (such as a 2D spline?) filled in the pixels in between. Each of the original 160x120 hardware pixels was turned into a 4x4 pixel grid where the edges of the grid were adjusted to fit better with neighboring 4x4 pixel grids. The PWCX appeared to support a higher frame rate because the PWCX module "decompressed" the true hardware pixels and filled in the pseudo-pixels on the other side of the USB wire.

We discovered the PWCX effect while taking entropy measurements of webcam frames. Using PWC alone in 160x120 mode, the webcam produced slightly more entropy than 640x480 PWCX mode. The PWCX module was not adding real image data to webcam frames, it was just smoothing and filling in data that looked good enough to a human. However, PWCX could not fool the math ... :-)

The PWC maintainer says on his web site:

" and I'm going to request (well, demand) that PWC will be removed from the kernel tree.''

The PWC maintainer's position appears to be that if you cannot use PWCX, then PWC is worthless. From LavaRnd's point of view, PWCX (the binary only module) adds no value and in some ways reduces the Logitech QuickCam's value as an entropy source.

We (LavaRnd) do not want to take sides in this PWC/PWCX kernel dispute. If this posting appears that way, then we apologize. The PWC folks have been mostly patient with our unusual use of their webcam modules. The Linux kernel folks have provided us with a wonderful platform for LavaRnd. As for ourselves, we put a lot of time into helping end users use the PWC module in older kernels.

Here is our advice request:

The LavaRnd project would like to see the PWC (open source) module remain in the Linux Kernel. We would like the Linux kernel folk to not honor the maintainer's request to remove everything. We want the support of PWC without PWCX to continue in the Linux Kernel. What is the best was to make this position / request known to the key Kernel people in the hopes they will PWC as part of Linux?

And does every chunk of the Linux Kernel need an active maintainer? Could PWC remain in the Linux Kernel without the original maintainer's support or would someone such as ourselves need to step up and offer to maintain it?

It was not hard for us to get approval to buy the Lava Lite lamps. Our bosses were very supportive in signing the purchase orders to buy the lamps. All it took was presenting a cool idea (lavarand) to cool bosses (David Watson and later Mel Pleasant). :-)

Some have asked about the relationship between the classic SGI lavarand and the current LavaRnd project:

• One of the members of the SGI classic lavarand team (me) is also on the current LavaRnd team
• As a nod to history, we do maintain a pair of lamps in view of the live image our entropy source.
• The difference between the old SGI classic lavarand and the new LavaRnd may be viewed here

You can find the name for "5 million trillion trillion" == 5e30 by using my English name of a number, an open source Perl program that can generate names of numbers of any size (e.g., the English name of the largest known prime).

In the above article, one could replace ''5 million trillion trillion pounds'' with:

• five nonillion pounds in the so-called American system
• five quintillion pounds in the so-called European system

And one could replace ''10 billion trillion trillion carats'' with:

• ten decillion carats in the so-called American system
• ten quintilliard carats in the so-called European system

You can find the name for "5 million trillion trillion" == 5e30 by using my English name of a number, an open source Perl program that can generate names of numbers of any size (e.g., the English name of the largest known prime).

In the above article, one could replace ''5 million trillion trillion pounds'' with:

• five nonillion pounds in the so-called American system
• five quintillion pounds in the so-called European system

And one could replace ''10 billion trillion trillion carats'' with:

• ten decillion carats in the so-called American system
• ten quintilliard carats in the so-called European system

Gregory W. Nemitz

I know that some feel that 8 links in 1 paragraph is excessive, but that's crap! It isn't enough! Shame on the poster, shame.

In fact there's a whole bunch of things you can do with the ANSI escape sequences. All you have to do is use \e for ESC (or \033 if octal is your thing.) bash also includes the \[ and \] meta-escape characters that you put around non-printing escape sequences to let the shell know that they're non-printing.

My bash prompt is currently:
PS1='\[\e]0;\l \w\007\]\n($?) \t \[\e[36m\]\l \[\e[32m\]\u@\h \[\e[33m\]\w\[\e[0m\]\n$ '

The "ESC]0;foo\007" bit sets the rxvt terminal title to the current tty and path. $? is the exit code of the last command, \t is the time, \l is the tty, \u is the user name, \h is the hostname, \w is the CWD. (All of these are in the bash info pages.)

My 37 Gemini page contains several images from the POSS2/UKSTU and the HST Phase 2 digital plate stacks.

Great mileage: You can drive it like a j-random normal 5-speed can and get about 63.5 MPG (3.7 L/100km). With a little practice and following some standard tips you can get a lot more. I usually get about 750 miles to 900 miles (about 1200 km to 1450 km) on a 11 US gal (41.6L) tank (68.1 MPG to 81.9 MPG == 3.45 L/100km to 2.87 L/100km).

Good pep: Pushed 108 MPH on a test track. Could have gone a bit higher but test track conditions were not the best. (Hint: your mileage suffers at that speed, so I don't recommend it that fast :-)). More than enough zip to make it onto a freeway with a short on-ramp.

Fun to drive. I love the idle stop feature (engine turns off under certain conditions). The digital display panel is well designed and can give you good feedback (out of the corner of you eye) what works

People really notice it, even after 2+ years. When gas prices in California push their way towards $2/Gal (and beyond :-( ), I start to get a lot more people asking about it.

I highly recommend a visit to the www.insightcentral.net for detailed info on the Honda Insight, pictures of internal guts, tips and tricks owner forum, mileage database, etc.

Our LavaRnd project does not use Lava Lite(R) lamps.

Well, OK, we do have a Live LavaCan image that is sitting between two (but unrelated to the project) Lava Lite lamps. :-)

A little known fact: the lamp on the left is the lamp that was used in the South Park: Bigger, Longer & Uncut movie trailer.

One of the SGI classic lavarand inventors (Bob Mende) is rebuilding the original classic site. Watch the LavaRnd news page for details.

So why do we call it LavaRnd? Well, one of the LavaRnd co-inventors likes to visit volcanoes, so we worked Lava into the name and site theme.

It is because one of the co-authors (Landon) of the lavarnd code likes bats.

Actually, there are words for really large numbers. And 2^128 isn't that large.

Here is the full number:
340282366920938463463374607431768211456

and here is how you pronounce it in the american system:
three hundred forty undecillion,
two hundred eighty two decillion,
three hundred sixty six nonillion,
nine hundred twenty octillion,
nine hundred thirty eight septillion,
four hundred sixty three sextillion,
four hundred sixty three quintillion,
three hundred seventy four quadrillion,
six hundred seven trillion,
four hundred thirty one billion,
seven hundred sixty eight million,
two hundred eleven thousand,
four hundred fifty six

or in the European system:
three hundred forty sextillion,
two hundred eighty two quintilliard,
three hundred sixty six quintillion,
nine hundred twenty quadrilliard,
nine hundred thirty eight quadrillion,
four hundred sixty three trilliard,
four hundred sixty three trillion,
three hundred seventy four billiard,
six hundred seven billion,
four hundred thirty one milliard,
seven hundred sixty eight million,
two hundred eleven thousand,
four hundred fifty six

try it yourself

I used my knowledge of Latin to help me write the Name of a Number Perl / CGI program. Now I know how to determine the English name of any integer of any size. While some dictionaries list names of numbers as large as 10^33 (one decillion) or even 10^63 (one vigintillion), it took a study of Latin before I was able to determine the name of numbers such as:

• 10^882 (one ducenttrenonagintillion)
• 10^1782 (one quingenttrenonagintillion)
• 10^9702 (one tremilliaducenttretrigintillion)
• 10^123456 (one unquadraginmilliacentunquinquagintillion)

You never know when you may need to give the English name of a large integer. It was almost 20 years after I discovered what was then (in 1979) the largest known prime 2^23209-1 before I knew how to pronounce the English name of its decimal representation. If I had studied Latin in more detail when I was in grade school then I would have been ready to answer the frequently asked question: "How do you pronounce it?"

1/2 :-)

I used my knowledge of Latin to help me write the Name of a Number Perl / CGI program. Now I know how to determine the English name of any integer of any size. While some dictionaries list names of numbers as large as 10^33 (one decillion) or even 10^63 (one vigintillion), it took a study of Latin before I was able to determine the name of numbers such as:

• 10^882 (one ducenttrenonagintillion)
• 10^1782 (one quingenttrenonagintillion)
• 10^9702 (one tremilliaducenttretrigintillion)
• 10^123456 (one unquadraginmilliacentunquinquagintillion)

You never know when you may need to give the English name of a large integer. It was almost 20 years after I discovered what was then (in 1979) the largest known prime 2^23209-1 before I knew how to pronounce the English name of its decimal representation. If I had studied Latin in more detail when I was in grade school then I would have been ready to answer the frequently asked question: "How do you pronounce it?"

1/2 :-)

I used my knowledge of Latin to help me write the Name of a Number Perl / CGI program. Now I know how to determine the English name of any integer of any size. While some dictionaries list names of numbers as large as 10^33 (one decillion) or even 10^63 (one vigintillion), it took a study of Latin before I was able to determine the name of numbers such as:

• 10^882 (one ducenttrenonagintillion)
• 10^1782 (one quingenttrenonagintillion)
• 10^9702 (one tremilliaducenttretrigintillion)
• 10^123456 (one unquadraginmilliacentunquinquagintillion)

You never know when you may need to give the English name of a large integer. It was almost 20 years after I discovered what was then (in 1979) the largest known prime 2^23209-1 before I knew how to pronounce the English name of its decimal representation. If I had studied Latin in more detail when I was in grade school then I would have been ready to answer the frequently asked question: "How do you pronounce it?"

1/2 :-)

I used my knowledge of Latin to help me write the Name of a Number Perl / CGI program. Now I know how to determine the English name of any integer of any size. While some dictionaries list names of numbers as large as 10^33 (one decillion) or even 10^63 (one vigintillion), it took a study of Latin before I was able to determine the name of numbers such as:

• 10^882 (one ducenttrenonagintillion)
• 10^1782 (one quingenttrenonagintillion)
• 10^9702 (one tremilliaducenttretrigintillion)
• 10^123456 (one unquadraginmilliacentunquinquagintillion)

You never know when you may need to give the English name of a large integer. It was almost 20 years after I discovered what was then (in 1979) the largest known prime 2^23209-1 before I knew how to pronounce the English name of its decimal representation. If I had studied Latin in more detail when I was in grade school then I would have been ready to answer the frequently asked question: "How do you pronounce it?"

1/2 :-)

Today using a new method we call lavarnd (instead of lavarand with 3 a's) that uses the thermal noise from digitial cameras. While they were cool the new method is smaller and does not use the lamps, only a small USB based digitial camera. Our new, patent free method can generate about 100 Kbits/sec off of a Logitech QuickCam 3000 Pro USB camera on a Linux system with ~1GHz CPU.

We hope to have the full site, complete with Open Source code and CGI demos (old and new) ready by Nov 2002.

There were many and frequent bright fireballs. During the peak of the storm (1015-1130 UTC), the sky was frequently filled with multiple meteors! Wow!

obfuscation is a noun

In a conversation with an OED editor, we learned that obfuscate in its various forms have been used as far back as 1577, but fell into disuse around 1900. The editor told us that their had been an increase of the use of the word in the early 1990's ... and traced part of the increase back to the IOCCC. :-)