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#include <iostream>
using namespace std;

int events[5005];
long long suma;
long long x[5005];
long long ans;
long long mod = 1e9 + 7;

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n;
    cin >> n;
    for (int i = 0; i < n; i++)
    {
        int a;
        cin >> a;
        events[a]++;
    }
    suma = 1;
    x[0] = 1;
    for (int i = 1; i <= 5000; i++)
    {
        for (int j = 0; j < events[i]; j++)
        {
            ans += suma;
            if (ans >= mod) ans -= mod;
            for (int k = 5001; k >= i - 1; k--)
            {
                suma += x[k];
                if (suma >= mod) suma -= mod;
                x[min (5001, k + i)] += x[k];
                if (x[min (5001, k + i)] >= mod) x[min (5001, k + i)] -= mod;
                
            }
        }
        suma -= x[i - 1];
        if (suma < 0) suma += mod;
    }
    cout << ans;
}