#include<bits/stdc++.h>
using namespace std;
#define endl '\n'
#define int long long
const int N = 1e5 + 10;
const int P = 1e9 + 7;
int a[N];
map<int, int>mp;

void solve() {
	int pos = 1;
	vector<int>ans[N];
	mp.clear();
	int n;
	cin >> n;
	for (int i = 1; i <= n; i++) cin >> a[i];
	for (int i = 1; i <= n; i++) {
		int tmp = i - a[i];
		if (mp.find(tmp) != mp.end()) {
			ans[mp[tmp]].push_back(a[i]);
		} else {
			mp[tmp] = pos++;
			ans[mp[tmp]].push_back(a[i]);
		}
	}
	int res = 0;
	for (int i = 1; i <= pos; i++) {
		sort(ans[i].begin(), ans[i].end());
		reverse(ans[i].begin(), ans[i].end());
		int l = ans[i].size();
		for (int j = 0; j <= l-2; j += 2) {
			int ce=ans[i][j]+ans[i][j+1];
			if(ce>0) res+=ce;
		}
	}
	cout<<res<<endl;

}

signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	int _ = 1;
	cin>>_;
	while (_--) {
		solve();
	}
	return 0;
}