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#include <iostream>
#include <cmath>
#include <vector>
#include <map>
#include <unordered_map>
#include <algorithm>
#include <cstdint>
#include <cstdio>
#include <cinttypes>

using namespace std;

map<vector<int>, bool> subsets;
map<int, int> occur;

vector<int> fact;

int modulo = pow(10, 9) + 7;

int sum(vector<int>& numbers) {
	int tot = 0;
	for (int num : numbers) {
		tot += num;
	}

	return tot;
}

void printVector(vector<int>& nums) {
	for (int num: nums) {
		cout << num << " ";
	}
	cout << endl;
}

bool calcSums(vector<int>& numbers, int add) {
	// cout << "[i] in calcSums ";
	// printVector(numbers);
	if (subsets.find(numbers) != subsets.end()
		&& subsets[numbers]) {
		if (add <= sum(numbers) + 1) {
			// cout << "good vector: ";
			// printVector(numbers);
			return true;
		} else {
			// cout << "bad vector: ";
			// printVector(numbers);
			return false;
		}
	}

	subsets[numbers] = false;

	for (int i = 0; i < numbers.size(); ++i) {
		vector<int> newNumbers = numbers;
		newNumbers.erase(newNumbers.begin() + i);
		if (calcSums(newNumbers, numbers[i])) {
			subsets[numbers] = true;
			// cout << "it was good!!" << endl;
		}
	}

	return subsets[numbers];
}

bool isSubsetValid(vector<int>& numbers) {
	//check if not already calculated
	if (subsets.find(numbers) != subsets.end()) {
		return subsets[numbers];
	}

	return subsets[numbers];
}

void calcSubsets(vector<int>& numbers) {
	int count = 0;
	uint64_t total;

	if (numbers.size() == 1) {
		if (numbers[0] == 1) {
			subsets[vector<int>{1}] = true;
		}
		return;
	}

	if (isSubsetValid(numbers)) {
		// cout << "already calculated ";
		// printVector(numbers);
		return;
	}

	for (int i = 0; i < numbers.size(); ++i) {
		vector<int> newNumbers = numbers;
		newNumbers.erase(newNumbers.begin() + i);
		calcSubsets(newNumbers);
	}

	//calculate
	if (calcSums(numbers, 0)) {
		subsets[numbers] = true;
	} else {
		subsets[numbers] = false;
	}

	return;
}

int calcBinomial(int n, int k) {
	// cout << n << " po " << k << endl;
	// cout << n << "! = " << fact[n] << endl;
	// cout << k << "! = " << fact[k] << endl; 

	uint64_t bin;
	bin = (uint64_t) fact[n];
	bin /= fact[k];
	bin /= fact[n-k];
	
	bin %= modulo;

	int res = bin;
	// cout << " = " << res << endl;
	return res;
}

int calcCombinations(map<int, int> localOccur) {
	uint64_t count = 1;
	for (auto it = localOccur.begin(); it != localOccur.end(); ++it) {
		count *= calcBinomial(occur[it->first], it->second);
		count %= modulo;
	}

	return count;
}

int findCombinations() {
	uint64_t total = 0;

	for (auto it = subsets.begin(); it != subsets.end(); ++it) {
		uint64_t cur = 0;
		if (it->second) {
			cur = 1;
			// cout << "good vector is ";
			map<int, int> localOccur;

			for (int num: it->first) {
				// cout << num << " ";
				if (localOccur.find(num) == localOccur.end()) {
					localOccur[num] = 0;
				}
				localOccur[num]++;
			}
			// cout << endl;
			cur = calcCombinations(localOccur);

			// cout << "in " << cur << "versions" << endl;
			total += cur;
			total %= modulo;
 		}
	}

	return total;
}

void calcFactorials(int n) {
	fact.push_back(1);
	int i = 1;
	while (i <= n) {
		fact.push_back(fact[i-1]*i % modulo);
		// cout << i << "! = " << fact[i] << endl;
		i++;
	}
}

int main() {
	int n;
	cin >> n;
	vector<int> numbers;

	int maxOccur = 0;
	for (int i = 0; i < n; ++i) {
		int num;
		cin >> num;
		if (num == 1) {
			subsets[vector<int>{1}] = true;
		}
		numbers.push_back(num);
		if (occur.find(num) == occur.end()) {
			occur[num] = 0;
		}
		occur[num]++;
		if (occur[num] > maxOccur) {
			maxOccur = occur[num];
		}
	}

	// cout << "max occur is " << maxOccur << endl;

	calcFactorials(maxOccur);
	//this will allow for easy access from the map,
	//as all subsets will be non-decreasing
	sort(numbers.begin(), numbers.end());
	calcSubsets(numbers);

	cout << findCombinations() << endl;

	return 0;
}