spoj#GF2. Irreducible polynomials over GF2
Irreducible polynomials over GF2
Find the number of degree n irreducible polynomials over GF(2). For example: for n=1 there are two such polynoms: x and x+1. For n=2 there is only one: x2+x+1. Note that in R[x] the polynom x2 +1 is irreducible, but not over GF(2), because x2+1=(x+1)*(x+1)
Input
A single positive integer n, where n<500000
Output
Output the answer for n.
Example
Input:
201
Output:
15989433276208858463104100421305100522608250813995004946218
Input:
1
Output:
2
Input:
2
Output:
1
Input:
3
Output:
2