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#include "bits/stdc++.h" // Tomasz Nowak
using namespace std;     // XIII LO Szczecin
using LL = long long;    // Poland
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
template<class T> int size(T &&x) {
	return int(x.size());
}
template<class A, class B> ostream& operator<<(ostream &out, const pair<A, B> &p) {
	return out << '(' << p.first << ", " << p.second << ')';
}
template<class T> auto operator<<(ostream &out, T &&x) -> decltype(x.begin(), out) {
	out << '{';
	for(auto it = x.begin(); it != x.end(); ++it)
		out << *it << (it == prev(x.end()) ? "" : ", ");
	return out << '}';
}
void dump() {}
template<class T, class... Args> void dump(T &&x, Args... args) {
	cerr << x << ";  ";
	dump(args...);
}
#ifdef DEBUG
  struct Nl{~Nl(){cerr << '\n';}};
# define debug(x...) cerr << (strcmp(#x, "") ? #x ":  " : ""), dump(x), Nl(), cerr << ""
#else
# define debug(...) 0 && cerr
#endif
mt19937_64 rng(0);
int rd(int l, int r) {
	return uniform_int_distribution<int>(l, r)(rng);
}
// end of templates

constexpr int mod = int(1e9) + 7;
int add(int a, int b) {
	a += b;
	if(a >= mod)
		a -= mod;
	return a;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	int n;
	cin >> n;
	vector<int> a(n);
	for(int &ai : a)
		cin >> ai;
	sort(a.begin(), a.end());
	debug(a);

	int max_a = a.back() + 1;
	vector dp(n, vector<int>(max_a));
	for(int i = 0; i < n; ++i) {
		int ai = a[i];
		if(i > 0)
			dp[i] = dp[i - 1];
		for(int sum = 1; i > 0 and sum < max_a; ++sum)
			if(sum + 1 >= ai) {
				int &rem = dp[i][min(sum + ai, max_a - 1)];
				rem = add(rem, dp[i - 1][sum]);
			}
		if(ai == 1)
			dp[i][ai] = add(dp[i][ai], 1);
	}
	debug(dp);

	int ans = 0;
	for(int sum = 0; sum < max_a; ++sum)
		ans = add(ans, dp.back()[sum]);
	cout << ans << '\n';
}