#include <bits/stdc++.h>
using namespace std;
long long arr[100000 + 100], n;
long long q_pow(long long x, long long y, const long long mod) {
  long long res = 1;
  while (y) {
    if (y & 1) res = res * x % mod;
    x = x * x % mod;
    y >>= 1;
  }
  return res;
}
signed main() {
  bool flag = false;
  cin >> n;
  for (int i = 1; i <= n; i++) cin >> arr[i];
  long long sum = 1;
  for (int i = 1; i <= n; i++) sum = arr[i] % 2 * sum % 2;
  if ((q_pow(2, (sum + 1) % 2, 3) + q_pow(-1, sum, 3)) % 3 == 0) flag = true;
  sum = 1;
  for (int i = 1; i <= n; i++) sum = arr[i] % 1000000006 * sum % 1000000006;
  long long temp1 = q_pow(2, (sum - 1 + 1000000006) % 1000000006, 1000000007) +
                    q_pow(-1, sum, 1000000007);
  if (flag) temp1 = q_pow(3, 1000000007 - 2, 1000000007) * temp1 % 1000000007;
  long long temp2 = q_pow(2, (sum - 1 + 1000000006) % 1000000006, 1000000007);
  if (!flag) temp2 = temp2 * 3 % 1000000007;
  cout << temp1 << "/" << temp2 << endl;
  return 0;
}
