#include <iostream>
#include <string>
#include <algorithm>
#include <utility>
#include <cmath>
#include <cstdlib>
#include <map>
#include <set>
#include <queue>
#include <vector>
using namespace std;
#define MOD 1000000007

long long modinv(long long a, long long mod) {
    long long b = mod, u = 1, v = 0;
    while (b) {
        long long t = a / b;
        a -= t * b; swap(a, b);
        u -= t * v; swap(u, v);
    }
    u %= mod;
    if (u < 0) u += mod;
    return u;
}

int main() {
	long long N; cin >> N;
	vector<long long> A(N);
	for (int i = 0; i < N; i++) cin >> A[i];
	long long sum = 0;
	for (long long i = 0; i < N; i++) {
        long long mul = modinv(A[i], MOD);
        for (long long j = 0; j < N; j++) {
            if (i == j) continue;
            mul = mul * modinv(abs(A[j] * A[j] - A[i] * A[i]) % MOD, MOD) % MOD;
        }
        if (i % 2 == 1) mul = MOD - mul;
        sum += mul;
	}
    cout << (sum % MOD) * modinv(2, MOD) % MOD << endl;
}