#include <bits/stdc++.h>
using namespace std;
long long int power(long long int a, long long int b) {
  long long int res = 1;
  a = a % 1000000007;
  while (b > 0) {
    if (b & 1) {
      res = (res * a) % 1000000007;
      b--;
    }
    a = (a * a) % 1000000007;
    b >>= 1;
  }
  return res;
}
long long int gcd(long long int a, long long int b) {
  return (b == 0) ? a : gcd(b, a % b);
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  string s;
  cin >> s;
  long long int n = s.length();
  long long int ans = 0;
  for (long long int i = 0; i < n; i++) {
    string cur = "";
    for (long long int j = 0; j < 9; j++) {
      if (i + j >= n) break;
      cur = s.substr(i, j + 1);
      int f = 0;
      for (long long int x = 0; x <= j; x++) {
        for (long long int k = 1; x + 2 * k <= j; k++) {
          if (cur[x] == cur[x + k] && cur[x] == cur[x + 2 * k]) {
            f = 1;
            break;
          }
        }
        if (f) break;
      }
      if (f) ans++;
    }
    ans += max(0LL, n - i - 9LL);
  }
  cout << ans;
}
