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#include<bits/stdc++.h>
using namespace std;

long long n, tab[200009];

bool check(long long k)
{
    long long ak = 0, bk = k, a, b, c, sum;
    for(int i=1; i<=n; i++) {
        a = 0;
        b = min(bk + 1, 201LL);
        while(a < b) {
            c = (a + b) / 2;
            sum = c * (c - 1) * (c - 2) + 3LL * c * (c - 1) * (ak + bk - c) + 6LL * c * ak * (bk - c);
            if(sum >= 6LL * tab[i]) b = c;
            else a = c + 1;
        }
        bk -= a;
        ak += a;
        sum = a * (a - 1) * (a - 2) + 3LL * a * (a - 1) * (ak + bk) + 6LL * a * ak * bk;
        if(ak > k || sum < 6LL * tab[i]) return false;
    }
    return true;
}

void solve()
{
    cin>>n;
    for(int i=1; i<=n; i++) cin>>tab[i];
    long long a = 3, b = 200 * n, c;
    while(a < b) {
        c = (a + b) / 2;
        if(check(c)) b = c;
        else a = c + 1;
    }
    cout<<a<<'\n';
    return;
}

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);
    int t;
    cin>>t;
    while(t--) solve();
    return 0;
}