#include <bits/stdc++.h>
using namespace std;
int t, n;
long long gcd(long long a, long long b) {
  if (!b) return a;
  return gcd(b, a % b);
}
int isPrime(long long a) {
  for (long long i = 2; i * i <= a; ++i)
    if (a % i == 0) return 0;
  return 1;
}
int main() {
  scanf("%d", &t);
  while (t--) {
    scanf("%d", &n);
    long long q = n, r = n + 1;
    while (!isPrime(q)) q--;
    while (!isPrime(r)) r++;
    long long nom = r * ((long long)q - 2) + 2L * ((long long)n - q + 1);
    long long den = 2L * q * r;
    long long g = gcd(nom, den);
    nom /= g;
    den /= g;
    printf("%I64d/%I64d\n", nom, den);
  }
  return 0;
}
