#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
int main ()
{
	int t,i,n;
	ll ans[35];
	ans[1] = 1,ans[2] = 3;
	while(scanf("%d",&t)==1)
	{
		while(t--)
		{
			scanf("%d",&n);
			for(i = 3;i<=n;i++) ans[i] = 2*ans[i-2]+ans[i-1];
			printf("%lld\n",ans[n]);
		}
	}
	return 0;
}

[题目链接] (http://acm.hdu.edu.cn/showproblem.php?pid=2501)