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#include<bits/stdc++.h>

using namespace std;

constexpr int N=5e3+5, P=1e9+7;

vector<int>tab;
long long dp[N], dwa[N];

int main()
{
	int n,a;
	long long ans=0;
	dp[0]=1;
	dwa[0]=1;
	scanf("%d", &n);
	for(int i=0;i<n;++i)
	{
		scanf("%d", &a);
		tab.push_back(a);
		dwa[i+1]=dwa[i]*2;
		dwa[i+1]%=P;
		//cout << "dwa[i]= " << dwa[i] << endl;
	}
	sort(tab.begin(), tab.end());
	int pozostale=n-1;
	for(auto e:tab)
	{
		//cout << "pozostale = " << pozostale << endl;
		//cout << "dwa pozostale = " << dwa[pozostale]  << endl;
		for(int i=N-5;i>=0;--i)
		{
			if(i>=e-1) //i=i-e
			{
				if(i+e<=5000)
				{
					dp[i+e]+=dp[i];
					dp[i+e]%=P;
				}
				else
				{
					ans+=dp[i]*dwa[pozostale];
					ans%=P;
				}
			}
			else
				break;
		}
		--pozostale;
		/*cout << "po dodaniu: " << e << endl;
		for(int i=1;i<20;++i)
		{
			cout << dp[i] << endl;
		}
		cout << "========" << endl;*/
	}
	for(int i=1;i<N;++i)
	{
		//cout << dp[i] << endl;
		ans+=dp[i];
		ans%=P;
	}
	printf("%lld", ans);
	return 0;
}