#include <bits/stdc++.h>
using namespace std;
const long long int N = 1e6 + 10;
const long long int inf = 1e9;
const long long int M = 1e9 + 7;
const long double Pi = 3.14159265;
string s;
long long int n, ans;
void solve() {
  cin >> s;
  n = s.length();
  for (long long int i = 0; i < n; i++) {
    for (long long int j = i + 2, k; j < n; j++) {
      for (k = 1; k < n; k++) {
        if (j - 2 * k < i) break;
        if (s[j] == s[j - k] and s[j - 2 * k] == s[j]) break;
      }
      if (j - 2 * k < i) continue;
      ans += n - j;
      break;
    }
  }
  cout << ans;
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  solve();
  long long int xx = 0;
  return 0;
}
