/**
* Author : Vu Khac Minh
**/
#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int maxn = 3e5 + 5;
const int mod = 1e9+7;
ll n,pre[maxn],suf[maxn],a[maxn],res,bit[maxn];
vector<ll> ctz;
void add(int u,int v)
{
for(;u<=n;u+=u&-u) bit[u]+=v;
}
ll get(int u)
{
ll sum = 0;
for(;u;u-=u&-u) sum+= bit[u];
return sum;
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin>>n;
for(int i = 1;i<=n;i++)
{
cin>>a[i];
ctz.push_back(a[i]);
}
sort(ctz.begin(),ctz.end());
ctz.erase(unique(ctz.begin(),ctz.end()));
for(int i = 1;i<=n;i++)
{
a[i] = lower_bound(ctz.begin(),ctz.end(),a[i]) - ctz.begin()+1;
pre[i] = get(a[i]-1);
add(a[i],1);
}
memset(bit,0,sizeof bit);
add(a[n],1);
for(int i = n-1;i>=2;i--)
{
res+= pre[i]* get(a[i]-1);
// cout<<i<<" "<<pre[i-1]<<" "<< get(a[i]-1)<<'\n';;
add(a[i],1);
}
cout<<res;
return 0;
}
