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#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

const int MOD = 1000000007;

int main()
{
    ios_base::sync_with_stdio(0);
    int n;
    cin >> n;
    vector<int> a(n);
    for (int i = 0; i < n; ++i)
        cin >> a[i];
    sort(a.begin(), a.end());
    vector< vector<int> > dp(n, vector<int>(5001, 0));
    for (int i = 0; i < n; ++i)
        if (a[i] == 1)
            dp[i][1] = 1;
    for (int i = 0; i < n - 1; ++i)
    {
        for (int j = 1; j <= 5000; ++j)
        {
            if (j != 5000)
            {
                dp[i + 1][j] = (dp[i + 1][j] + dp[i][j]) % MOD;
                if (a[i + 1] <= j + 1)
                {
                    int nast = min(5000, j + a[i + 1]);
                    dp[i + 1][nast] = (dp[i + 1][nast] + dp[i][j]) % MOD;
                }
            }
            else
                dp[i + 1][j] = (dp[i + 1][j] + 2 * dp[i][j] % MOD) % MOD;
        }
    }
    int odp = 0;
    for (int i = 1; i <= 5000; ++i)
        odp = (odp + dp[n - 1][i]) % MOD;
    cout << odp;
    return 0;
}