ll f[16]={1};
rep(i,1,16)f[i]=f[i-1]*i;

ll@n,@m;
ll a[16]={0,1};
ll b[16];
rep(i,2,16){
	ll z=0;
	rep(j,i){
		z+=f[i]/(f[j]*f[i-j])*a[j];
	}
	a[i]=i**n-z;
}
wt(a[m]);