help with series and succesions (math)?

Question

write an expression for the most apparent nth term of the squence (assume that n begins with 1).


1,2,6,24,120,...

Answer 1

f(n) = n!
= n*(n-1)*(n-2)...*2*1

since f(1) = 1, f(2) = 2*1 = 2, f(3) = 3*2*1 = 6, f(4) = 4*3*2*1 = 24, etc.
or f(n) = n*f(n-1)

Answer 2

n!

1! = 1
2! = 2x1=2
3! = 3*2*1 = 3*2! = 6
4! = 4*3*2*1 = 4*3! = 24
5! = 120 etc

The sequence is simply n! (n factorial)

Answer 3

n!