B - Halum Halum Permutation:

#include<stdio.h>

long long dp[1000007];

void pre()
{
    dp[1]=1;
    dp[2]=1;
    dp[3]=3;
    for(int i=4; i<=1000002; i++){
        dp[i] = i*dp[i-1] + i*dp[i-2] - dp[i-1] - 2*dp[i-2];
        dp[i] = dp[i] % 1000000007;
    }
}

int main()
{
    //freopen("in.txt","r",stdin);
    //freopen("out.txt","w",stdout);
    pre();
    int css,cs;
    scanf("%d",&css);
    for(cs=1; cs<=css; cs++){
        int a;
        scanf("%d",&a);
        printf("Case %d: %lld\n",cs,dp[a]);
    }

    return 0;
}