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#include <bits/stdc++.h>
#define PB push_back
#define ST first
#define ND second
#define _ ios_base::sync_with_stdio(0); cin.tie(0);
//mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

using namespace std;

using ll = long long;
using pi = pair<int,int>;
using vi = vector<int>;

const int nax = 5000 + 10, mod = 1e9 + 7;
int n;
int a[nax];
int dp[nax][nax];
int mx;

int main() {_
	cin >> n;
	for(int i = 1; i <= n; ++i) {
		cin >> a[i];
		mx = max(mx, a[i]);
	}
	sort(a + 1, a + n + 1);
	int ans = 0;
	dp[0][0] = 1;
	for(int i = 1; i <= n; ++i) {
		ans = (ans + ans) % mod;
		for(int s = 0; s <= mx; ++s) {
			dp[i][s] = dp[i - 1][s];
			if(s >= a[i] && s - a[i] >= a[i] - 1) {
				dp[i][s] = (dp[i][s] + dp[i - 1][s - a[i]]) % mod;
			}
			if(s + a[i] > mx && s >= a[i] - 1) {
				ans = (ans + dp[i - 1][s]) % mod;
			}
		} 
	}
	for(int s = 0; s <= mx; ++s) {
		ans = (ans + dp[n][s]) % mod;
	}
	ans--;
	if(ans < 0) ans += mod;
	cout << ans;
	
}