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Surely once it gets alled a "PIN number", it's not geeky any more?

Haha true!

Agreed!

Jesus. "Pin Number" what kind of geeks are you? :(

Pinheads, ha ha!

Extra geek cred for me because I tried to click the blue text in the comic.

me too!

Same here :)

So you had to look something up? So much for being a geek...

AHHHH PIN Number makes it's feared return haha

*its

What, no 1729? Come on, you're slacking. :)

Seriously! Ramanujan rocks!

Kaprekar's constant is 6174 :(

Oops, my bad. Will fix it later ;-)

Thanks for pointing that out!

Second the 1729. Great comic!

those number with interesting mathematical properties are so cool i had to look them up on wiki in disbelief :)

(btw wiki mentions another Munchausen number which is 438579088 = 4^4 + 3^3 + 8^8 + 5^5 + 7^7 + 9^9 + 0^0 + 8^8 + 8^8, i guess they take the convention that 0^0 = 0)

Good point. van Berkel's preprint discusses Munchausen numbers in more detail (using bases other than 10 as well). In case anyone is looking for it, the wikipedia link is under a different name, namely "perfect digit-to-digit invariants".

I read the van Berkel paper, and the first statement in the first lemma is already wrong :-),

The claims he makes in both lemmas are false, but the lemmas are still true. So the result he was trying to prove still holds.

The result seems rather intuitive to me though.

Or rather, it should only take a bit of thought and perhaps a bit of scratching on some paper to convince yourself. (Here, I am referring to the fact that such numbers are finite in number. Finding tight bounds is obviously harder and less intuitive)

surely you should know 0^0 isn't defined

Depends on how you're defining exponents. If you're defining them in the common set-theoretical way that x^y = # of maps from a set of y elements into a set of x elements than 0^0 clearly is 1, there's exactly one map from an empty set into an empty set: the empty map.

Use L'Hopital's rule.

0^0 = 1

But surely 0 to any power is 0.

0^0=1 not 0

Actually 0^0 does not equal 1 because with every number you have X^a/X^b where a=b, then you get your power equation of X^a/X^b where you can simplify by X^(a-b). In this instance you have 0^a/0^b where a=b, in any case you still get a divide by zero error. Therefore 0^0 is undefined

Sorry to break it to you, guys, but 0^0=a pair of glasses. B-p

what happened to 1729?

3142, since it should really be called a PI-Number.

Thats good ... that's geekyness that normal people would get :)

got me LOL

I recently dicovered that 3^3+4^3+5^3=6^3 :-)

Nice!

What I knew was

10*9*8=6*5*4*3*2*1

I think (and I'm too lazy to actually check) that 10^2 + 11^2 + 12^2 = 13^2 + 14^2

Yeeeah! Mine's 6174 =D

What about 1024?

lulz too easy.

SWEET! I love this!

Personal Identification Number numbers for use at the Automated Teller Machine machines!

Forget the standard mod-n ackerman function or whatever, 1969 is the year of the moon landings! :D

1969 is also the year of the first moon landing.

Damnit! second.

Haha, I thought you were criticizing Person for saying moon landings in plural form

Fibonacci sequence?

Nah, that works better as a computer password.

What about 0047? Another "Star Trek" number.

Why-o-why would you call it a PIN Number? Personal Identification Number Number?

Saying PIN Number makes it clear exactly what I'm talking about and is commonly used (even though not quite correct). You can blame my RAS syndrome.

Real geeks don't get things like that wrong. So screwing it up ruins the whole effort.

Of the above, only 1969 is number base independent.

Oh Yeah? Try representing it in octal system :P

Now when you get a geek's bank card you can narrow down what pins to try.

1969 -- Also for Apollo 11, the 'mazing Mets and Bryan Adams! (okay, so you have to be a

sportsgeek or amusicgeek for the last two.But 1969 was one small deposit for savings one giant withdrawal from my checking.

What about 1077, the price of a cheese pizza and large soda at Panucci's Pizza?

3141? The most famous of als nerdnumbers...

as biologist, always loved the golden ratio, 1.618

0^0 is actually undefined. Get a math book ...look it up.

how about 5117. (the 5 being leet for S makes it a halo reference)

Use L'Hopital's Rule.

Mi wifi password; 11235813 xD

How about 1984?

The answer to 1984 is 1776!

What about 142857? Multiply it by any number but multiples of seven for a rearrangement but continual order of the digits.

...seven does cool stuff too.

personal identification number.....number?

Crap! I have used 42 in my PINs before.

personal Identification number number , just as bad as ATM machine.

4^4 + 3^3 + 8^8 + 5^5 + 7^7 + 9^9 + 0^0 + 8^8 + 8^8

= 256 + 27 + 16777216 + 3125 + 823543 + 387420489 + 0 + 16777216 + 16777216 = 438579088

^_^

RAM memory xD

What about 2600?

What about 5,318,008? That spells "Boobies" upsdide down on a calculator.

I use Kaprekar's constant as my copy code at work (I'm a math teacher) :P I also use it in a few other places... I win in geek.

I just tried the Kaprekar's Constant with 3291 and checked my math... it didn't work

You stopped too soon, 3291 reaches 6174 in 6 iterations. Also you may have forgotten the leading zero at step 5.

I was on holiday recently and used the first 8 significant figures of pi*e as the code on my hotel room safe. Long enough to be secure, not as obvious to guess as pi or e, easy as pie for both me and my roommate to calculate without writing it down anywhere.

Now that I've given away the secret, mathematicians everywhere will use that code for their room safes, and I'll be able to sneak in and steal their proofs.

It is still geeky...and don't call me Shirley.

Since enough people were disagreeing about this, consider the limits of the two following functions as x->0:

x^0

0^x

They can't both be continuous simultaneously, so pick your favorite. That's the value of 0^0.

9351 does NOT work, just sayin.

9351

9531-1359=8172

8721-1278=7443

7443-3447=3996

9963-3699=6264

6642-2466=4176 (look familiar?)

7641-1467=6174 (oh snap, it does!)

Reaches singularity in six iterations. Check yo' math (and that you're actually following the algorithm)

An interesting catch-->

Assume any 4 digit number with the digits in increasing order of 1 from left to right (Ex: 1234, 2345, etc). The difference between the larger number and the lower number will always lead to 3087 which, if repeated like the steps 2 & 3 as explained in the infographic above will always lead to 6174 just in 3 steps.

Ex: Number: 4567

1) 7654 - 4567 = 3087

2) 8730 - 0378 = 8352

3) 8532 - 2358 = 6174

2520 is a cool one as well: you can divide it by every number between 1 and 10 :)

heh u forgot 8008 !!

Well, to be honest, my Pin is 1337...

The 4 digit number I like is 1961. It is the last year until 6119 that is the same upside down. I don't think I am going to live that long.

i don't get it? (explain it easier and maybe some people that don't get it might. Cause I don't understand o.k i am talking about the last one at the bottom)

недорогой прокат авто и аренда автомобиля только тут

12+23+34+45+56+67+78+89

= 0404

:D

who's the geek? you are!

438579088 is also a Munchausen number

**(if we take 0^0 =0)

Calling the Enterprise "A starship in Star Trek" is like calling Bruce Wayne "A Batman." The Enterprise is THE Star Trek starship. Whenever anyone thinks Star Trek, they think of the Enterprise, and vice-versa.

Also, no 2814? Earth's designated section of space in the Green Lantern Corps? What about 6022, in reference to Avogadro's number (6.022 x 10^23)? Or 2001, referencing A Space Odyssey, the greatest scifi movie ever made? Seriously, there are so many directions to go with this.

I want this as a poster! My students would love it.