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#include <bits/stdc++.h>
#include <bits/extc++.h>

using namespace std;
using namespace __gnu_pbds;

#define _DEBUG
#ifdef _DEBUG
template<typename T1, typename T2> auto& operator<<(ostream& o, pair<T1, T2> a) { return o << "(" << a.first << ", " << a.second << ")"; }
template<typename T, typename OS> auto& operator<<(OS& o, T a) { o << "{"; for (auto b : a) o << b << ", "; return o << "}"; }
#define dbg(x...) cerr << "[" #x "]: ", [](auto... args) { ((cerr << args << ", "),...) << "\n"; }(x)
#else
#define dbg(...)
#endif

#define sz(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define F first
#define S second

template<class T>
using iset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
using ll = long long;
using ld = long double;
using pll = pair<ll,ll>;
using vi = vector<int>;

ll n;
vector<ll> v;

ll cnt(ll a, ll l, ll k) {
    ll a1 = a*l*(k-l-a);
    ll a2 = a*(a-1)*(k-a)/2;
    ll a3 = a*(a-1)*(a-2)/6;
    return a1+a2+a3;
}

bool solve(ll k) {
    ll lcnt = 0;

    for(ll i = 0 ; i < n ; ++i) {
        ll l = 0, r = k-lcnt;
        while(l < r) {
            ll mid = (l+r)/2;
            if(cnt(mid, lcnt, k) >= v[i]) r = mid;
            else l = mid+1;
        }
        if(cnt(l, lcnt, k) < v[i])
            return false;
        lcnt += l;
    }

    return true;
}

int main() {
    cin.tie(0)->sync_with_stdio(0);

    ll t;
    cin >> t;
    while(t--) {
        cin >> n;
        v = vector<ll>(n);
        for(ll i = 0 ; i < n ; ++i) cin >> v[i];

        ll l = 0, r = n+2007;
        while(l < r) {
            ll mid = (l+r)/2;
            if(solve(mid)) r = mid;
            else l = mid+1;
        }
        cout << l << '\n';
    }

    return 0;
}