hdu 1329 Hanoi Tower Troubles Again!

找规律的题目an=an-1+(i+i%2)/2*2;

#include<iostream>
#include<stdio.h>
#include<algorithm>
#include<iomanip>
#include<cmath>
#include<string>
using namespace std;
int main()
{
    int i,j,ans[51];
    ans[1]=1;
    for(i=2;i<=50;i++)
    {
        ans[i]=ans[i-1]+(i+i%2)/2*2;
    }
    int n,t;
    cin>>t;
    while(t--)
    {
        cin>>n;
        cout<<ans[n]<<endl;
    }
    return 0;
}