求（x+y+z）^n各个展开的系数，和幂 1<n<=15
 k1+k2+k3=n 
#include<cstdio>
#include<iostream>
using namespace std;
long long  fac[] = {1,1,2,6,24,120,720,5040,40320,362880,3628800,39916800,479001600,6227020800,87178291200,1307674368000};
int main()
{
    int n;
    while(~scanf("%d",&n))
    {
        for(int i=0;i<=n;i++)
            for(int j=0;j<=n;j++)
                for(int k=0;k<=n;k++)
        {
            if((i+j+k)==n)
            {
                printf("%d %d %d %lld\n",i,j,k,fac[n]/fac[i]/fac[j]/fac[k]);
            }
        }
    }
    return 0;
}