#include <iostream>
#include <vector>
#include <string>
#include <iomanip>
#include <queue>
#include <cmath>
#include <algorithm>
#include <tuple>
#include <iomanip>
#include <stdio.h>
#include <numeric>
#include <map>
#include <bitset>
#include <set>
#include <stack>
#include <queue>
#include <unordered_set>
#include <cassert>


//#pragma GCC optimize("Ofast,no-stack-protector")
//#pragma GCC optimize("O3")
//#pragma GCC target("avx2")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC optimize("fast-math")
//#pragma GCC optimize("section-anchors")
//#pragma GCC optimize("profile-values,profile-reorder-functions,tracer")
//#pragma GCC optimize("vpt")
//#pragma GCC optimize("rename-registers")
//#pragma GCC optimize("move-loop-invariants")
//#pragma GCC optimize("unswitch-loops")
//#pragma GCC optimize("function-sections")
//#pragma GCC optimize("data-sections")
//#pragma GCC optimize("branch-target-load-optimize")
//#pragma GCC optimize("branch-target-load-optimize2")
//#pragma GCC optimize("btr-bb-exclusive")
//#pragma GCC optimize("O0")


#define int long long
#define ll long long
#define ull unsigned long long
#define all(a) a.begin(), a.end()
#define pii pair<int, int>
#define pb push_back
#define ld long double


using namespace std;

//const int INF = 1e13;
//const int mod = 2600000069;
//const int p = 179;

int n;
vector<int> a, t_was, t_inv2;

void update(vector<int>& t, int v, int l, int r, int pos, int val) {
    if (r - l == 1) {
        t[v] += val;
        return;
    }
    int m = (l + r) / 2;
    if (pos < m) {
        update(t, 2 * v + 1, l, m, pos, val);
    } else {
        update(t, 2 * v + 2, m, r, pos, val);
    }
    t[v] = t[2 * v + 1] + t[2 * v + 2];
}

int get_sum(vector<int>& t, int v, int l, int r, int askl) {
    if (r <= askl) {
        return 0;
    }
    if (l >= askl) {
        return t[v];
    }
    int m = (l + r) / 2;
    return get_sum(t, 2 * v + 1, l, m, askl) + get_sum(t, 2 * v + 2, m, r, askl);
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n;
    t_was.assign(4 * n, 0);
    t_inv2.assign(4 * n, 0);
    a.resize(n);
    for (auto& k : a) cin >> k;
    vector<int> b = a;
    sort(all(b));
//    int k = 0;
//    for (int i = 1; i < n; i++) {
//        k += (b[i] != b[i-1]);
//    }
//    assert(k == n - 1);
    map<int, int> ind;
    for (int i = 0; i < n; i++) ind[b[i]] = i;
    int ans = 0;
    for (int i = 0; i < n; i++) {
        ans += get_sum(t_inv2, 0, 0, n, ind[a[i]] + 1);
        update(t_inv2, 0, 0, n, ind[a[i]], get_sum(t_was, 0, 0, n, ind[a[i]] + 1));
        update(t_was, 0, 0, n, ind[a[i]], 1);
    }
    cout << ans;
}
/*
 3
 3 2 1
 -> 1

 3
 2 3 1
 -> 0

 4
 10 8 3 1
 -> 4

 4
 1 5 4 3
 -> 1
*/