#include <bits/stdc++.h>
using namespace std;
const double EPS = 1e-8;
const int mod = 1e9 + 7;
const int N = 1e6 + 10;
const long long INF = 1e18;
long long power(long long x, long long y, long long mod) {
  long long t = 1;
  while (y > 0) {
    if (y % 2)
      y -= 1, t = t * x % mod;
    else
      y /= 2, x = x * x % mod;
  }
  return t;
}
long long A[N];
int main() {
  int k;
  scanf("%d", &k);
  int o = 1, th = 1;
  long long d = 1;
  for (int i = 0; i < k; ++i) {
    scanf("%lld", &A[i]);
    if (A[i] % 2 == 0) o = 0;
    d = d * (A[i] % (mod - 1)) % (mod - 1);
  }
  d = power(2, d, mod);
  th = power(2, o, 3);
  d = d * power(2, mod - 2, mod) % mod;
  th = (th * 2) % 3;
  int g = 1;
  if (o)
    g = -1, th -= 1;
  else
    th += 1;
  th = (th % 3 + 3) % 3;
  long long n = (d + g + mod) % mod;
  if (!th)
    n = n * power(3, mod - 2, mod) % mod;
  else
    d = d * 3 % mod;
  printf("%lld/%lld\n", n, d);
  return 0;
}
