#include <bits/stdc++.h>
#define BIT(n) (1LL << (n))
#define BITF(n, i) (((n) >> i) & 1)
#define REP(i, n) for (int i = 0; i < n; i++)
#define REPB(i, n) for (int i = 0; i < BIT(n); i++)
#define REPS(i, x) for (int i = 1; i <= x; i++)
#define REPR(i, n) for (int i = n; i >= 0; i--)
#define REPZ(i, x) for (int i = 0; i <= x; i++)
#define FOR(i, m, n) for (int i = m; i < n; i++)
#define FORA(i, n) for (auto &&i : n)
#define FORS(i, m, n) for (int i = m; i <= n; i++)
using namespace std;
#define PRINTARR(x, y)                                     \
  cerr << #x << "=\n";                                     \
  for (auto itr = x; itr != y; itr++) cerr << *itr << " "; \
  cerr << endl;
#define PRINTARR2(x, i0, i1)                                       \
  cerr << #x << "=\n";                                             \
  for (int ii0 = 0; ii0 < i0; ii0++) {                             \
    for (int ii1 = 0; ii1 < i1; ii1++) cerr << x[ii0][ii1] << " "; \
    cerr << endl;                                                  \
  }
#define DUMPOUT cerr
// vector
template <typename T> istream &operator>>(istream &is, vector<T> &vec) {
  for (T &x : vec) is >> x;
  return is;
}
// pair
template <typename T, typename U> ostream &operator<<(ostream &os, pair<T, U> &pair_var) {
  os << "(" << pair_var.first << ", " << pair_var.second << ")";
  return os;
}
// vector
template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) {
  os << "{";
  REP(i, (int)vec.size())
  os << vec[i] << (i + 1 == (int)vec.size() ? "" : ", ");
  os << "}";
  return os;
}
// map
template <typename T, typename U> ostream &operator<<(ostream &os, map<T, U> &map_var) {
  os << "{";
  FORA(itr, map_var) {
    os << *itr;
    itr++;
    if (itr != map_var.end()) os << ", ";
    itr--;
  }
  os << "}";
  return os;
}
// set
template <typename T> ostream &operator<<(ostream &os, set<T> &set_var) {
  os << "{";
  FORA(itr, set_var) {
    os << *itr;
    itr++;
    if (itr != set_var.end()) os << ", ";
    itr--;
  }
  os << "}";
  return os;
}
void dump_func() { DUMPOUT << endl; }
template <class Head, class... Tail> void dump_func(Head &&head, Tail &&... tail) {
  DUMPOUT << head;
  if (sizeof...(Tail) > 0) DUMPOUT << ", ";
  dump_func(std::move(tail)...);
}
#ifdef DEBUG_
#define DEB
#define DUMP(...)                                                             \
  DUMPOUT << "  " << string(#__VA_ARGS__) << ": "                             \
          << "[" << to_string(__LINE__) << ":" << __FUNCTION__ << "]" << endl \
          << "    ",                                                          \
      dump_func(__VA_ARGS__)
#else
#define DEB if (false)
#define DUMP(...)
#endif

#define ALL(v) v.begin(), v.end()
#define fst first
#define snd second
#define mp make_pair
#define pb push_back
#define epb emplace_back
#define int long long
#define pint pair<int, int>
#define ld long double
using namespace std;
template <class T> bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> bool chmin(T &a, const T &b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> using vec = std::vector<T>;
template <class T> void print(const T &x) { cout << x << "\n"; }
#define MAXQ 2500
vector<bool> isPrime(MAXQ + 1, false);
vector<int> pList;
int sizeP;

int pairV(int x) {
  int val = 1;

  for (int i = 0; i < sizeP; i++) {
    int cnt = 0;
    int primeV = pList[i];
    while (1) {
      if (x % primeV == 0) {
        x /= primeV;
        cnt++;
      } else {
        break;
      }
    }
    if (cnt == 1)
      val *= pList[i] * pList[i];
    else if (cnt == 2)
      val *= pList[i];
    if (x == 1) break;
  }

  int sqX = sqrt(x);
  if (sqX * sqX == x)
    val *= sqX;
  else
    val *= x * x;
  return val;
}
signed main() {
  cin.tie(0), ios::sync_with_stdio(false);
  cout << fixed << setprecision(10);
  int N;
  cin >> N;
  vec<int> s(N);
  REP(i, N) cin >> s[i];

  fill(isPrime.begin(), isPrime.end(), true);
  isPrime[0] = isPrime[1] = false;
  for (int i = 2; i <= MAXQ; ++i) {
    if (isPrime[i]) {
      pList.push_back(i);
      for (int j = i * 1LL * i; j <= MAXQ; j += i) {
        isPrime[j] = false;
      }
    }
  }
  //  DUMP(count(ALL(isPrime), true));

  map<int, int> ma;
  sizeP = pList.size();

  REP(i, N) {
    int val = s[i];
    int index = 0;
    while (val != 1 && index < sizeP) {
      int val2 = pow(pList[index], 3);
      if (val % val2 == 0) {
        val /= val2;
      } else {
        index++;
      }
    }
    ma[val]++;
  }

  int ans = 0;

  FORA(e, ma) {
    int v0 = e.fst;
    if (v0 == 1) {
      ans++;
      continue;
    }
    int v1 = pairV(v0);
    ans += max(ma[v0], ma[v1]);
    ma[v0] = ma[v1] = 0;
  }
  print(ans);
}

Measured memory_bytes: 15232