#include <bits/stdc++.h>
#define ll long long
#define pb push_back

using namespace std;

int main()
{
    ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);

    int t = 1;
    cin >> t;
    while(t-->0)
    {
        int n;
        cin >> n;

        vector<int> a(n);
        for(int i=0; i<n; i++) cin >> a[i];

        unordered_map<int, int> val;
        ll ans = 0;
        for(int i=n-1; i>=0; i--)
        {
            int x = a[i];

            if(x>0&&val[x-i]==0) val[x-i] = x;
            else if(val[x-i]!=0)
            {
                if(val[x-i] + x > 0) ans += val[x-i] + x;
                val.erase(x-i);
            }
        }

        cout << ans << "\n";
    }
}