#include <bits/stdc++.h>
const int mod = 1e9 + 7;
int mul(int x, int y) { return 1LL * x * y % mod; }
int qpow(int x, int y) {
  int res = 1;
  while (y) {
    if (y & 1) res = mul(res, x);
    y >>= 1;
    x = mul(x, x);
  }
  return res;
}
inline int read() {
  int x = 0, f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    x = x * 10 + ch - '0';
    ch = getchar();
  }
  return x * f;
}
using namespace std;
const int maxn = 1e5 + 15;
int N, dp[maxn][2], K;
int main(int argc, char *argv[]) {
  cin >> K;
  int mf = 1, odd = 0, even = 0, s = 1;
  for (int(i) = (1); (i) <= (K); ++(i)) {
    long long x;
    cin >> x;
    x %= (mod - 1);
    mf = 1LL * mf * x % (mod - 1);
    s = 1LL * s * x % 2;
    if (x & 1)
      ++odd;
    else
      ++even;
  }
  mf = (mf - 1 + mod - 1) % (mod - 1);
  if (s % 2 == 1) {
    printf("%d/%d\n", mul(qpow(3, mod - 2), (qpow(2, mf) - 1 + mod) % mod),
           qpow(2, mf));
  } else {
    printf("%d/%d\n", mul(qpow(3, mod - 2), (qpow(2, mf) + 1 + mod) % mod),
           qpow(2, mf));
  }
  return 0;
}
