http://acm.hdu.edu.cn/showproblem.php?pid=1249
f(n)=f(n-1)*(n-1)
View Code
1 #include <stdio.h>
2 const int N=10001;
3 int f[N]={0,2};
4 int main()
5 {
6 int T,i;
7 scanf("%d",&T);
8 for (i=2;i<N;i++) f[i]=f[i-1]+6*(i-1);
9 while (T--)
10 {
11 int n;
12 scanf("%d",&n);
13 printf("%d\n",f[n]);
14 }
15 }
