Cyclic Permutation

Before you see this post,

see

Permutation, Symmetric Group and Signature

Let's calculate cyclic permutations.

Permutation, Symmetric Group and Signature

Factorial, Permutation and Combination

n! -> n factorial

0! = 1 

   nPr -> n permutation r 

nPn = n!

n ≥ r

nPr means the number of methods 

to choose r different elements among n different elements 

with order.

nCr -> n combination r

      n ≥ r     

nCr means the number of methods
to choose r different elements among n different elements
without order.

if you want to more about factorial, permutation and combination

click

Factorial

Permutation

and

Combination