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Hm, never knew that, or seen <>.

Rochey wrote:Hm, never knew that, or seen <>.

It's a computer programming item for 'not equal to' is commonly used in BASIC languages.

Ah, right.

IanKennedy wrote:It's called factorial and, as Shran has just pointed out, you calculate it by multiplying all the integer numbers from 1 to the number specified together. For example:

1! = 1
2! = 1 x 2 = 2
3! = 1 x 2 x 3 = 6
4! = 1 x 2 x 3 x 4 = 24
5! = 1 x 2 x 3 x 4 x 5 = 120
6! = 1 x 2 x 3 x 4 x 5 x 6 = 720
7! = 1 x 2 x 3 x 4 x 5 x 6 x 7 = 5,040
8! = 1 x 2 x 3 x 4 x 5 x 6 x 7 x 8 = 40,320
9! = 1 x 2 x 3 x 4 x 5 x 6 x 7 x 8 x 9 = 362,880
10! = 1 x 2 x 3 x 4 x 5 x 6 x 7 x 8 x 9 = 3,628,800

as you can see factorials get big very very quickly, even faster than geometric progressions.

What are geometric progressions anyway? So if someone asks you to caluclate 4 factorial, they mean 4! or 1x2x3x4?

So if someone asks you to caluclate 4 factorial, they mean 4! or 1x2x3x4

Um... they're the same thing.

When I was in high school and I figured out the ! function on my calculator, I thought that it might make a cool basis for a warp scale. It would be a bit slow though.

stitch626 wrote:

So if someone asks you to caluclate 4 factorial, they mean 4! or 1x2x3x4

Um... they're the same thing.

Thats what I meant. They mean 4! which is 1x2x3x4. Oughta help me out if that ever comes up in Scholastic Scrimmage.

Yeah, 4! = 4 factorial.

I'm a Yank, and I've never seen "!=" used as "=/=." I think perhaps Ian is right, and your confusing progamming notation with proper mathematical notation.

Besides, be quiet. Aren't you a history teacher?

I reserve the right to bitch about anything, regardless of my knowledge on said matter.

You'll make someone a good wife one day.

Thank you.

A geometric progression, or geometric series, is one were you multiply the previous result by a fixed constant, so with a constant of 2 the sequence would go as follows:

1 x 2 = 2
2 x 2 = 4
4 x 2 = 8
8 x 2 = 16
16 x 2 = 32
32 x 2 = 64
64 x 2 = 128
128 x 2 = 256 etc.

This very common is life. For example things like bacteria multiply at a given rate. Each bacteria will divide into two copies of it's self, say once a second. So in this example you start with 1 bacteria and after the first second you end up with 2, then after another second you end up with 4, then 8, then 16, 32, 64, 128, 256 etc. The constant doesn't have to be 2 it can be anything even numbers less than 1, for example radioactive material has a half life. This means that if you start with say 100,000 atoms of the material at the end of the half life you will only have 50,000 left, after another period 25,000, then 12,500, 6,250 etc. To write it out in full it would look like this:

100,000 x 0.5 = 50,000
50,000 x 0.5 = 25,000
25,000 x 0.5 = 12,500
12,500 x 0.5 = 6,250
6,250 x 0.5 = 3,125 etc.

As I say the constant can be anything you like. Another one you are extremely familiar with, but may not have realised it, is multiples of 10:

1 x 10 = 10
10 x 10 = 100
100 x 10 = 1000
1000 x 10 = 10000
10000 x 10 = 100000
100000 x 10 = 1000000

Which you use every day, as it's the place values for digits in a base 10 numbering system, ie units, tens, hundreds, thousands...

Lazar wrote:When I was in high school and I figured out the ! function on my calculator, I thought that it might make a cool basis for a warp scale. It would be a bit slow though.

It would be slower at low warp than that used in TOS, which was a cubic scale, but significantly faster for higher numbers. Basically, the speed in multiples of the speed of light was given by the cube of the warp factor. So warp 4 would be 4³ = 64c; warp 10 would be 10³ = 1,000c. With factorial it would be as follows:

Warp = Warp! (TOS)
1 = 1c (1c)
2 = 2c (8c)
3 = 6c (27c)
4 = 24c (64c)
5 = 120c (125c)
6 = 720c (216c)
7 = 5,040c (343c)
8 = 40,320c (512c)
9 = 362,880c (729c)
10 = 3,628,800c (1,000c)

I wish I could do tables

IanKennedy wrote:...I wish I could do tables

Not my thing, but hey, you're an administrator.