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#include <cstdio>
#include <vector>

using namespace std;

int n;
unsigned int p = 1000000007;

vector<int> a;

typedef struct {
        int val;
        int num;
} node;

vector<node> b;

const int max_val = 5001;
const int max_n = 5001;

void print_b()
{
        for(unsigned int i = 0; i < b.size(); ++i) {
                printf("%d - %d\n", b[i].val, b[i].num);
        }
}

unsigned int newt[max_n][max_n];
unsigned long long s[max_val * max_n];
unsigned long long s2[max_val * max_n];
int lasts;


void calc_newt()
{
        for(int i = 1; i < max_n; ++i) {
                newt[i][0] = 1;
                newt[i][i] = 1;
        }

        for(int i = 2; i < max_n; ++i) {
                for(int j = 1; j < i; ++j) {
                        newt[i][j] = (newt[i-1][j-1] + newt[i-1][j]) % p;
                }
        }

}

void print_s()
{
        for(int i = 1; i <= lasts; ++i) {
                if (s[i] > 0) {
                        printf(" (%d - %llu)", i, s[i]);
                }
        }
        printf("\n");
}

void clean_s2(int a, int b)
{
        for(int i = a; i <=b; ++i) {
                s2[i] = 0;
        }
}

unsigned long long calc_s()
{
        unsigned long long result = 0;

        for(int x = 1; x <= b[0].num; ++x) {
                s[x] = newt[b[0].num][x];
        }

        lasts = b[0].num;

        for(auto it = b.begin()+1; it != b.end(); ++it) {
                int val = it->val;
                int num = it->num;
                
                clean_s2(val+val-1, lasts);
                
                for(int x = 1; x <= num; ++x) {

                        unsigned int count = newt[num][x];
                        unsigned int sum = val*x;

                        for(int i = val-1; i <= lasts; ++i) {
                                s2[sum+i] = (s2[sum+i] + (s[i]*count % p)) % p;
                        }
                }

                for(int i = val+val-1; i <= val*num+lasts; ++i) {
                        s[i] = (s[i] + s2[i]) % p;
                }
                lasts = val*num+lasts;
          //      print_s();
        }

        for(int i = 1; i <= lasts; ++i) {
                result = (result + s[i]) % p;
        }
        return result;
}

int main()
{       
        scanf("%d", &n);

        a.resize(max_val);
        for(int i = 0; i < n; ++i) {
                int x;

                scanf("%d", &x);
                a[x]++;
        }

        for(int i = 1; i < max_val; ++i) {
                node nd;

                if (a[i] > 0) {
                        nd.val = i;
                        nd.num = a[i];
                        b.push_back(nd);
                }
        }

        if (b[0].val != 1) {
                printf("0\n");
                return 0;
        }

        calc_newt();

        printf("%llu\n", calc_s());

        //print_s();

        return 0;
}