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#include <iostream>
#include <math.h>
#include <stdio.h>
#include <string>
#include <map>
#include <stdlib.h>
#include <vector>
#include <cstring>
#include <algorithm>  

using namespace std;


int constantt = 1000000007;

unsigned long long  modFact(unsigned long long  n) 
{ 
    unsigned long long  p  = constantt;
    //if (n >= p) 
    //    return 0; 
  
    unsigned long long  result = 1; 
    for (unsigned long long  i = 1; i <= n; i++) 
        result = (result * i) % p; 
  
    return result; 
} 

unsigned long long comp(unsigned long long  k, unsigned long long  n) {
    unsigned long long nsil = modFact(n);
    unsigned long long ksil = modFact(k);
    unsigned long long nmksil = modFact(n - k);
    unsigned long long res = (nsil / (ksil * nmksil) );
    return res;
}

unsigned long long
gcd(unsigned long long x, unsigned long long y)
{
    while (y != 0)
    {
        unsigned long long t = x % y;
        x = y;
        y = t;
    }
    return x;
}

unsigned long long
choose(unsigned long long n, unsigned long long k)
{
    if (k > n)
        throw std::invalid_argument("invalid argument in choose");
    unsigned long long r = 1;
    for (unsigned long long d = 1; d <= k; ++d, --n)
    {
        unsigned long long g = gcd(r, d);
        r /= g;
        unsigned long long t = n / (d / g);
        if (r > std::numeric_limits<unsigned long long>::max() / t)
           throw std::overflow_error("overflow in choose");
        r *= t;
    }
    return r;
}

unsigned long long calc2(std::map<int, int> & map, int index, int suma) {
    int range = suma + 1;
    std::map<int, int>::iterator iter = map.begin();
    std::advance(iter, index);  
    if (iter == map.end()) {
        return 1;
    } else {
        if (iter->first > range) {
            return 0; 
        }

        unsigned long long result = 0;
            if (iter->second == 1) {
                result++;
            }
        for (int i = 1; i <= iter->second; i++) {
            unsigned long long mnoznik = choose( iter->second, i);
            //printf("mnoznik: %d dla %d z %d\n", mnoznik, i, iter->second);
            //printf("Wywoluje suma = %d Obecny : %d a jest go : %d Obecny res: %d\n", suma + i * iter->first, iter->first, iter->second, result);
            unsigned long long wynik = calc2(map, index + 1, suma + i * iter->first);
            //printf("result dla %d: obecny result: %d wynik %d * %d Dylo ich: %d\n",iter->first, result, wynik, mnoznik, i);
            result += mnoznik * wynik;
            result %= constantt;
             

        }
        return result % constantt;
    }
    return 1;
}

unsigned long long calc(std::map<int, int> & map) {
    int ileJedynek = map[1];
    unsigned long long result = 0;
       if (ileJedynek == 1) {
                result++;
            }
    for (int i = 1; i <= ileJedynek; i++) {
        unsigned long long mnoznik = choose( ileJedynek, i);
        //printf("mnoznik: %d dla %d z %d\n", mnoznik, i, ileJedynek);
        //printf("Wywoluje dla jedynek suma = %d\n", i);
        
        result +=  mnoznik * calc2(map, 1, i);
        result %= constantt;
    }
    return result % constantt;
}

int main() {
    int edges = 15;
	scanf("%d", &edges);

    vector<int> map;
    for (int i = 0 ; i < edges; i++) {
        int tmp;
        scanf("%d", &tmp);
        map.push_back(tmp);
    }

    std::map<int, int> mapp;
    for (int i = 0 ; i < map.size(); i++) 
    {
        mapp[map[i]]++;
    }

    if (mapp.count(1) == 0) {
        printf("0");
    } else {
        unsigned long long res = calc(mapp);
        res %= constantt;
        printf("%llu", res);
    }

    return 0;
}