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Carmine
03-05-2005, 12:44 PM
I was just reading a link someone posted to help me in figuring out combinations. Is there a shortcut to solving N! other than 52x51x50.....etc. I don't recall seeeing calculators with this function key, but never specifically looked either.

gaming_mouse
03-05-2005, 01:31 PM
Almost any good scientific calculator will have a n! key, as well as an nCr key for doing (n choose r). Also, google calculator supports these functions.

Try typing "9!" or (52 choose 2) into google. It can handle REALLY big numbers too.

HTH,
gm

alThor
03-05-2005, 02:02 PM
[ QUOTE ]
Try typing "9!" or (52 choose 2) into google. It can handle REALLY big numbers too.

[/ QUOTE ]

Interestingly, it seems to have the exact same limits as Excel, i.e. it pukes as soon as the answer gets in the area of 2^2^10. It would have been cool for Google to go one bit higher, just to snub M$. Unless I am missing something fundamental about computer engineering, it would be essentially costless for Google to have done that.

alThor

gaming_mouse
03-05-2005, 02:12 PM
[ QUOTE ]

Interestingly, it seems to have the exact same limits as Excel,

[/ QUOTE ]

Really? I havn't used excel in a while, but it seemed like Google could go a lot higher from what I remember. Can Excel do 170!

AngusThermopyle
03-05-2005, 02:38 PM
Unless I am missing something fundamental about computer engineering,

2^1024 - 1 is the maximium double using 8 byte doubles.

MickeyHoldem
03-05-2005, 02:47 PM
both excel and google can do 170!

neither can do 171!

OrianasDaad
03-05-2005, 04:41 PM
The scientific calculator provided with windows handles these numbers. Start->Run... CALC

It handles numbers greater than 170! as well.

Carmine
03-05-2005, 05:43 PM
Great. Thanks guys!

Siegmund
03-06-2005, 05:46 AM
If you are working with a hand calculator or some similar medium that doesn't like numbers the size of 52!, you can always use the old-fashioned pre-computer standby:

ln n! ~ n ln n - n.

jason_t
03-06-2005, 10:36 AM
Also, n! ~ (n/e)^n * sqrt(2*pi*n). The first step in the derivation of this amazing formula is establish that ln n! ~ n ln n - n, which is not hard if you know calculus.