# include <iostream>
using namespace std; // 超时，但是只有十个数字
int main()
{
    int n;
    int a[11] = {0, 1, 0, 0, 2, 10, 4, 40, 92, 352, 724};
    while(cin >> n)
    {
        if(n == 0)
        break;
        cout << a[n] << endl;
    }
    return 0;
}

#include<iostream>
#include<fstream>
using namespace std;
int a[16];
int n, sum;
bool f(int x)
{
    for(int i = 1; i < x; i++)
    {
        if(abs(x - i) == abs(a[x] - a[i]) || a[x] == a[i])
        return false;
    }
    return true;
}
int dfs(int x)
{
    if(x > n && n > 0)
        sum += 1;
    else
    {
        for(int i = 1; i <= n; i++)
        {
            a[x] = i;
            if(f(x))
            dfs(x + 1);
        }
    }
    return sum;
}
int main()
{
    //fstream cin("aaa.txt");
    while(cin >> n)
    {
        if(n == 0)
        break;
        sum = 0;
        cout << dfs(1) << endl;
    }
    return 0;
}