Basics
One of the main things about statistics is the sum denoted by the greek letter sigma. A sum is simply the sum of all the values in a series between any 2 points in the function.
Combinatorics
A factorial can be defined as all whole numbers smaller multiplied together, for example 4!(the ! represents factorial) would equal 1 * 2 * 3 * 4, likewise 8! would equal 1 * 2 * 3 * 4 * 5 * 6 * 7 * 8.
| 1! |
1 |
| 2! |
2 |
| 3! |
6 |
| 4! |
24 |
| 5! |
120 |
| 6! |
720 |
| 7! |
5040 |
| 8! |
40320 |
| 9! |
362880 |
| 10! |
3628800 |
Using this we can define 2 new functions, combinations and permutations.
