#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 polynomials: x and x+1. For n=2 there is only one: x2+x+1. Note that in R[x] the polynomials 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</p>Output: 15989433276208858463104100421305100522608250813995004946218
Input: 1 Output: 2
Input: 2 Output: 1
Input: 3 Output: 2