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#include <queue>
#include <iostream>
#include <vector>
#include <cstring>
#include <iostream>
//#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn = 1e6 + 10;
int segment_tree[maxn];

void build(int node, int L, int R) {
    if(L == R) {
        segment_tree[node] = 0;
    }
    else {
        int mid = (L + R) / 2;
        build(2 * node, L, mid);
        build(2 * node + 1, mid + 1, R);
        segment_tree[node] = segment_tree[2 * node] + segment_tree[2 * node + 1];
    }
}
int query(int node, int L, int R, int i, int j) {
    // L R i L R j L R
    if(i <= L and R <= j) {
        return segment_tree[node];
    }
    if(R < i or j < L) {
        return 0;
    }
    int mid = (L + R) / 2;
    return query(2 * node, L, mid, i, j) + query(2 * node + 1, mid + 1, R, i, j);
}
void update(int node, int L, int R, int idx) {
    if(L == R) {
        segment_tree[node] += 1;
        return;
    }
    int mid = (L + R) / 2;
    if(idx <= mid) {
        update(2 * node, L, mid, idx);
    }
    else {
        update(2 * node + 1, mid + 1, R, idx);
    }
    segment_tree[node] = segment_tree[2 * node] + segment_tree[2 * node + 1];
}
int main() {
    ios_base::sync_with_stdio(false);
    int n;
    cin >> n;
    vector<int> v(n);
    vector<pair<int, int> > compressed;
    for(int i = 0; i < n; i++) {
        cin >> v[i];
        compressed.push_back(make_pair(v[i], i));
    }
    sort(compressed.begin(), compressed.end());
    vector<int> tmp;
    for(int i = 0; i < n; i++) {
        tmp.push_back(compressed[i].second);
    }
    reverse(tmp.begin(), tmp.end());
    build(1, 0, n);
    vector<ll> smaller;
    for(int i = 0; i < n; i++) {
        update(1, 0, n, tmp[i]);
        smaller.push_back(query(1, 0, n, 0, tmp[i] - 1));
    }
    build(1, 0, n);
    vector<ll> bigger;
    for(int i = n - 1; i >= 0; i--) {
        update(1, 0, n, tmp[i]);
        bigger.push_back(query(1, 0, n, tmp[i] + 1, n));
    }
    reverse(bigger.begin(), bigger.end());
    
    ll res = 0;
    for(int i = 0; i < n; i++) {
        res += bigger[i] * smaller[i];
    }
    cout << res << endl;
    return 0;
}