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 Output: 15989433276208858463104100421305100522608250813995004946218
Input: 1 Output: 2
Input: 2 Output: 1
Input: 3 Output: 2
hide comments
[Trichromatic] XilinX:
2009-05-26 08:31:50
I've solved this problem in MIPT Online Judge by Ruby, but it seems that Ruby works pretty slow in SPOJ. Last edit: 2009-05-26 02:21:16 |
|
Robert Gerbicz:
2009-05-26 08:31:50
Java and Python are too slow on this problem. You can try c/c++ or haskell. |
Added by: | Robert Gerbicz |
Date: | 2009-05-25 |
Time limit: | 0.100s-1s |
Source limit: | 4096B |
Memory limit: | 1536MB |
Cluster: | Cube (Intel G860) |
Languages: | All except: ERL JS-RHINO |
Resource: | classic problem, own input |