#include <bits/stdc++.h>
using namespace std;
const int N = 1 << 20;
long long sum;
int k, p, n, a[N + 1], i, b[N + 1], left_tree[N + 1], right_tree[N + 1];
vector<long long> leftv, rightv;
void update(int index, int value, int tree[]) {
  while (index < N + 1) {
    tree[index] += value;
    index += (index & -index);
  }
}
int read(int index, int tree[]) {
  int sum = 0;
  while (index > 0) {
    sum += tree[index];
    index -= (index & -index);
  }
  return sum;
}
int main() {
  cin >> n;
  for (i = 0; i < n; i++) {
    cin >> a[i];
    b[i] = a[i];
  }
  sort(b, b + n);
  for (i = 0; i < n; i++) {
    a[i] = upper_bound(b, b + n, a[i]) - b;
  }
  for (i = 0; i < n; i++) {
    update(a[i], 1, left_tree);
    leftv.push_back(read(N, left_tree) - read(a[i], left_tree));
  }
  for (i = n - 1; i >= 0; i--) {
    rightv.push_back(read(a[i], right_tree));
    update(a[i], 1, right_tree);
  }
  reverse(rightv.begin(), rightv.end());
  for (i = 0; i < n; i++) {
    sum += rightv[i] * leftv[i];
  }
  cout << sum;
}
