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#include <iostream>
#include <algorithm>
#include <vector>
#include <stack>
using namespace std;

vector<int> breakpoints;
unsigned currentBreakpoints;

int BST(int start, int end, int val) {
	if (start == end) {
		return start;
	}
	
	int mid = (start + end) / 2;
	if (breakpoints[mid] < val) {
		return BST(mid + 1, end, val);
	} else {
		return BST(start, mid, val);
	}
}

int getNextBreakpointPos(int val) {
	return BST(0, currentBreakpoints - 1, val);
}

int main() {
	ios_base::sync_with_stdio(0);
	int n, a;
	const long long p = 1000000007;
	long long *howMany;
	int *partialSums;
	int *values;
	
	cin >> n;
	
	partialSums = new int[n];
	values = new int[n];
	
	for (int i = 0; i < n; ++i) {
		cin >> a;
		values[i] = a;
	}
	
	sort(values, values + n);
	
	partialSums[0] = 0;
	for (int i = 0; i < n; ++i) {
		partialSums[i] = partialSums[i - 1] + values[i - 1];
	}
	
	
	howMany = new long long[partialSums[n - 1] + 1];
	for (int i = 0; i < partialSums[n - 1] + 1; ++i) {
		howMany[i] = 0;
	}
	stack<pair<int, long long>> howManyToAdd;
	
	breakpoints.push_back(0);
	breakpoints.push_back(partialSums[n - 1] + 1);
	
	for (int i = n - 1; i >= 0; --i) {
//		cout << "processing " << i << endl;
		
		currentBreakpoints = breakpoints.size();
		
		if (i == n - 1) {
			howMany[values[i] - 1] = 1;
			breakpoints.push_back(values[i] - 1);
		} else {
			for (int j = values[i] - 1; j <= partialSums[i]; ) {
				int breakPos1 = getNextBreakpointPos(j + 1);
				int breakPos2 = getNextBreakpointPos(j + values[i] + 1);
				
				int break1 = breakpoints[breakPos1];
				int break2 = breakpoints[breakPos2];
				
				int dist1 = break1 - j;
				int dist2 = break2 - j - values[i];
				
				int minDist = min(dist1, dist2);
				
				howManyToAdd.push(make_pair(j, (1 + howMany[breakpoints[breakPos1 - 1]] + howMany[breakpoints[breakPos2 - 1]]) % p));
				
				if (j != breakpoints[getNextBreakpointPos(j)]) {
					breakpoints.push_back(j);
				}
				
				j += minDist;
			}
			
			while (!howManyToAdd.empty()) {
				howMany[howManyToAdd.top().first] = howManyToAdd.top().second;
				howManyToAdd.pop();				
			}
		}
		
		sort(breakpoints.begin(), breakpoints.end());
		
		/*for (int j = 0; j <= partialSums[n - 1]; ++j) {
			cout << "(" << i << "," << j << "): " << howMany[j] << "  ";
		}
		cout << endl;*/
	}
		
	cout << howMany[0] << endl;
		
	delete [] partialSums;
	delete [] howMany;
	delete [] values;
	
	return 0;
}