What is Largest Factorial n! computed?

Post by l. Palmer
After 5 hours it's at 7,580!

Don't want to make you feel bad...<vbg> but the program Mathematica agrees
with your assesment so far in 0.01 seconds...

Timing[Length[IntegerDigits[7580!]]]

{0.012*Second, 26,119}

Really makes you wonder how they do that! Any program that I would write
wouldn't come close to that timing either. :>)
--
Dana
Using Windows XP & Office XP
= = = = = = = = = = = = = = = = =

Post by l. Palmer
Just goofing with numbers, I'm running a program I made to calculate
factorials n!
1*2*3*4 ...
After 5 hours it's at 7,580! and the result is 26,119 digits long.
My program will crash when the result reaches 65K digits.
I'm just curious if anybody knows what the largest computed factorial is.
LP

Laurence Reeves

2003-09-13 08:29:26 UTC

Post by Dana

Post by l. Palmer
After 5 hours it's at 7,580!

Don't want to make you feel bad...<vbg> but the program Mathematica agrees
with your assesment so far in 0.01 seconds...
Timing[Length[IntegerDigits[7580!]]]
{0.012*Second, 26,119}
Really makes you wonder how they do that! Any program that I would write
wouldn't come close to that timing either. :>)

I'd like to know too!

When I put together my "ECalc" proglet (on the website), I never did
find a satisfactory (accurate to 315,643 digits) way to calculate it.

--
Lau
http://www.bergbland.info
Get a domain from http://oneandone.co.uk/xml/init?k_id=5165217 and I'll
get the commission!

l. Palmer

2003-09-13 13:17:27 UTC

0.012 sec is pretty cool.

Like I said, I'm not a math wiz and am just goofing with numbers and don't
feel bad about the 0.012 second result.
It was a first time run. Does Mathematica give you all 26,119 digits?
LP

Post by Dana

Post by l. Palmer
After 5 hours it's at 7,580!

Don't want to make you feel bad...<vbg> but the program Mathematica agrees
with your assesment so far in 0.01 seconds...
Timing[Length[IntegerDigits[7580!]]]
{0.012*Second, 26,119}
Really makes you wonder how they do that! Any program that I would write
wouldn't come close to that timing either. :>)
--
Dana
Using Windows XP & Office XP
= = = = = = = = = = = = = = = = =

Patrick Hamlyn

2003-09-13 07:35:14 UTC

I suppose you do realise that after calculating 100! you can then calculate 101!
just by multiplying by 101?

I wouldn't ask, but 5 hours... seems like you must be starting from 1 each time
or something.

--
Patrick Hamlyn posting from Perth, Western Australia
Windsurfing capital of the Southern Hemisphere
Moderator: polyforms group (polyforms-***@egroups.com)

Steve Grant

2003-09-13 13:01:34 UTC

Post by Patrick Hamlyn
I suppose you do realise that after calculating 100! you can then calculate 101!
just by multiplying by 101?
I wouldn't ask, but 5 hours... seems like you must be starting from 1 each time
or something.

In order to understand recursion, you must first understand recursion.

Bob Pease

2003-09-13 18:28:15 UTC

Post by Patrick Hamlyn
I suppose you do realise that after calculating 100! you can then

calculate 101!

Post by Patrick Hamlyn
just by multiplying by 101?
I wouldn't ask, but 5 hours... seems like you must be starting from 1

each

Post by Patrick Hamlyn
time

Post by Patrick Hamlyn
or something.

In order to understand recursion, you must first understand recursion.

How fun!!
A two-sided Mad Magazine recursive cascade...

In order to understand "In order to understand recursion, you must first
understand recursion" must first understand recursion

In order to understand "In order to understand "In order to understand
recursion, you must first understand recursion" must first understand
recursion" you must first understand recursion.

Next??

RJ P

Proginoskes

2003-09-14 03:09:01 UTC

Post by Patrick Hamlyn
I suppose you do realise that after calculating 100! you can then

calculate 101!

Post by Patrick Hamlyn
just by multiplying by 101?
I wouldn't ask, but 5 hours... seems like you must be starting from 1

each
time

Post by Patrick Hamlyn
or something.

In order to understand recursion, you must first understand recursion.

This isn't recursion; it's an infinite loop.

Post by Patrick Hamlyn
How fun!!
A two-sided Mad Magazine recursive cascade...
In order to understand "In order to understand recursion, you must first
understand recursion" must first understand recursion

To be grammatically correct:

In order to understand "In order to understand recursion, you must first
understand recursion", you must first understand recursion.

Post by Patrick Hamlyn
In order to understand "In order to understand "In order to understand
recursion, you must first understand recursion" must first understand
recursion" you must first understand recursion.
Next??

To make sense of the quotation marks, we should do it the "English" way:

In order to understand "In order to understand 'In order to understand
recursion, you must first understand recursion" must first understand
recursion' you must first understand recursion.

and then you can say:

In order to understand '''In order to understand "In order to understand
'In order to understand recursion, you must first understand recursion"
you must first understand recursion', you must first understand recursion''',
you must first understand recursion.

And:

In order to understand ''''In order to understand '''In order to understand
"In order to understand 'In order to understand recursion, you must first
understand recursion" you must first understand recursion', you must first
understand recursion''', you must first understand recursion'''', you must
first understand recursion.

And I think you get the point. (It's not too difficult to construct, of
course.)
-- Christopher Heckman

Bob Pease

2003-09-14 21:27:03 UTC

Post by Proginoskes

Post by Patrick Hamlyn
I suppose you do realise that after calculating 100! you can then

calculate 101!

Post by Patrick Hamlyn
just by multiplying by 101?
I wouldn't ask, but 5 hours... seems like you must be starting from 1

each
time

Post by Patrick Hamlyn
or something.

In order to understand recursion, you must first understand recursion.

This isn't recursion; it's an infinite loop.

In order to understand "In order to understand recursion, you must first
understand recursion", you must first understand recursion.

In order to understand "In order to understand 'In order to understand
recursion, you must first understand recursion" must first understand
recursion' you must first understand recursion.
In order to understand '''In order to understand "In order to understand
'In order to understand recursion, you must first understand recursion"
you must first understand recursion', you must first understand recursion''',
you must first understand recursion.
In order to understand ''''In order to understand '''In order to understand
"In order to understand 'In order to understand recursion, you must first
understand recursion" you must first understand recursion', you must first
understand recursion''', you must first understand recursion'''', you must
first understand recursion.
And I think you get the point. (It's not too difficult to construct, of
course.)
-- Christopher Heckman

Sounds like someone is talking with a lisp.

Actually ( even if I left out the word "you" ( oops),
the statement is A rather peculiar tautology ( A===> A) ( but funny,
anyway) as stated.

consider
"in order to under the STATEMENT " in order to understand recursion, you
must first understand recursion" you must first understand recursion "

bears merit as being properly structured, and a Candidate for a cascade even
if only one-sided..

The original one I remember is
"The guy who wrote the letters to the editor should write the letters
himself".

R J Pease

mensanator

2003-09-13 16:35:24 UTC

I suppose you do realise that after calculating 100! you can then calculate 101!
just by multiplying by 101?
I wouldn't ask, but 5 hours... seems like you must be starting from 1 each time
or something.

Even my Python program (by no means a speed demon) got

time to calculate 0.25

for 7580!

But when I print the number to the screen...

time to print 6.17199993134

So you can speed things up considerably by avoiding screen I/O. And if
you really need to see the 26,119 digits, you'll find that writing
them to a file is much quicker.

2003-09-14 19:53:18 UTC

Post by mensanator
Even my Python program (by no means a speed demon) got
time to calculate 0.25
for 7580!
But when I print the number to the screen...
time to print 6.17199993134
So you can speed things up considerably by avoiding screen I/O. And if
you really need to see the 26,119 digits, you'll find that writing
them to a file is much quicker.

Python script running on a 1.8 P4 in PythonWin interactive window
calculated and displayed 7580! in less than 1 second. Unfortunately, it
takes a lot longer than that to scroll down to the end of all 29,000+
digits. :-) The first 10 are: 1902546043... Neat feature of Python is
that it has "built-in" big number capability. Size of integers is
limited only by amount of system memory (on my machine, 512MB).

Patrick O'Donnell

2003-09-18 15:10:44 UTC