#include <bits/stdc++.h>
using namespace std;
long long n;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  string s;
  cin >> s;
  n = (long long)s.length();
  long long cnt = 0;
  for (long long l = 0; l < n - 2; l++) {
    bool nemu = 0;
    for (long long r = l + 2; r < n; r++) {
      for (long long k = 1; k + k + l <= r; k++) {
        for (long long mul = l; mul + k + k <= r; mul++) {
          if (s[mul] == s[mul + k] && s[mul] == s[mul + k + k]) {
            nemu = 1;
            break;
          }
        }
        if (nemu) break;
      }
      if (nemu) {
        cnt += n - r;
        break;
      }
    }
  }
  cout << cnt << '\n';
  return 0;
}
