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#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("fractii.in");
ofstream fout("fractii.out");
int N, cnt=0;
int x[20];
int cmmdc(int a, int b)
{
while(a!=b)
{
if(a>b)
a=a-b;
else
b=b-a;
}
return b;
}
int valid(int k)
{
for(int i=1;i<k;i++)
if(cmmdc(x[i], x[k])!=1)
return 0;
return 1;
}
void back(int k)
{
for (int i = 1; i <= N; i++)
{
x[k] = i;
if (valid(k))
if (k == 2)
cnt++;
else
back(k + 1);
}
}
int main()
{
fin >> N;
back(1);
fout << cnt;
return 0;
}