#include <bits/stdc++.h>
using namespace std;
mt19937_64 rd(787);
int a[500010];
int cnt[500010];
unsigned long long has[500010];
unsigned long long val[500010];
list<int> vec[500010];
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  auto t = clock();
  auto now_time = [&] { return (clock() - t) / (double)CLOCKS_PER_SEC; };
  int n;
  cin >> n;
  unsigned long long anss = 1e18;
  for (int i = 1; i <= n; i++) cin >> a[i];
  while (now_time() < 4) {
    for (int i = 1; i <= n; i++) val[i] = rd(), vec[i].clear();
    unsigned long long ans = 0;
    map<unsigned long long, int> mp;
    mp[0]++;
    int pre = 0;
    for (int i = 1; i <= n; i++) {
      int tmp = a[i];
      has[i] = has[i - 1] + val[tmp], cnt[tmp]++, vec[tmp].push_back(i);
      if (cnt[tmp] % 3 == 0) {
        has[i] -= 3 * val[tmp];
      }
      mp[has[i]]++;
      if (vec[tmp].size() > 3) {
        int now = vec[tmp].front();
        vec[tmp].pop_front();
        for (; pre < now; pre++) {
          mp[has[pre]]--;
        }
      }
      ans += mp[has[i]] - 1;
    }
    anss = min(ans, anss);
    break;
  }
  cout << anss << endl;
}
