#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 3e5 + 5, mod = 1e9 + 7;
const ll inf = 9e18;
int n, h[N], bit[N], ans[N];
ll tmp[N];
vector <ll> val;
void up(int idx, int vl) {
while (idx <= n) bit[idx] += vl, idx += -idx & idx;
}
int get(int idx) {
int res = 0;
while (idx > 0) res += bit[idx], idx -= -idx & idx;
return res;
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0);
// freopen(".INP", "r", stdin);
// freopen(".OUT", "w", stdout);
cin >> n;
for (int i = 1; i <= n; ++i) cin >> tmp[i], val.push_back(tmp[i]);
sort(val.begin(), val.end());
val.erase(unique(val.begin(), val.end()), val.end());
ll kq = 0;
for (int i = 1; i <= n; ++i) {
h[i] = lower_bound(val.begin(), val.end(), tmp[i]) - val.begin() + 1;
ans[i] = get(h[i] - 1);
up(h[i], 1);
}
fill(bit, bit + n + 1, 0);
for (int i = n; i >= 1; --i) {
kq += 1LL * ans[i] * get(h[i] - 1);
up(h[i], 1);
}
cout << kq;
}
