#include<stdio.h>
#include<string.h>
#include<algorithm>
#include<math.h>

using namespace std;
typedef long long ll;
#define MAXN 105

ll z[MAXN];

int main()
{
    z[1]=3;
    z[2]=9;
    for(int i=3;i<=40;i++)
        z[i]=2*z[i-1]+z[i-2];
    int t;
    scanf("%d",&t);
    while(t--)
    {
        int n;
        scanf("%d",&n);
        printf("%lld\n",z[n]);
    }
    return 0;
}