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#include <cstdio>
#include <cstring>
#include <cmath>
#include <cassert>
#include <iostream>
#include <algorithm>
#include <iterator>
#include <string>
#include <vector>
#include <queue>
#include <bitset>
#include <utility>
#include <stack>

using namespace std;
typedef long long LL;
typedef pair<int,int> PII;
typedef vector<int> VI;
#define MP make_pair
#define FOR(v,p,k) for(int v=(p);v<=(k);++v)
#define FORD(v,p,k) for(int v=(p);v>=(k);--v)
#define REP(i,n) for(int i=0;i<(n);++i)
#define VAR(v,i) __typeof(i) v=(i)
#define FOREACH(i,c) for(VAR(i,(c).begin());i!=(c).end();++i)
#define PB push_back
#define ST first
#define ND second
#define SIZE(x) (int)x.size()
#define ALL(c) c.begin(),c.end()

#define ODD(x) ((x)%2)
#define EVEN(x) (!(ODD(x)))

#define MAX_A 5000
int t[MAX_A+1];
const int modulo = 1000000007;

inline void add_modulo(int &x, int y) {
    x = (x+y) % modulo; 
}

int main() {
    int n;
    scanf("%d\n", &n);
    VI ta;
    ta.reserve(n);
    REP(i, n) {
        int a;
        scanf("%d", &a);
        ta.PB(a);
    }
    sort(begin(ta), end(ta));
    int res = 0;
    t[0] = 1;
    int cum_sum = 0;
    REP(i, n) {
        int a = ta[i];
        FORD(i, cum_sum, a-1) {
            add_modulo(res, t[i]);
        } 
        FORD(i, cum_sum, a-1) {
            add_modulo(t[min(MAX_A, a+i)], t[i]);
        }
        cum_sum = min(MAX_A, cum_sum + a);
    }

    printf("%d\n", res);
    return 0;
}