#include <bits/stdc++.h>
using namespace std;
const int N = 3e5 + 20;
long long a[N];
int main() {
  string s;
  cin >> s;
  long long cnt = 0;
  long long n = s.size();
  for (int i = 0; i < n; i++) {
    long long indx = -1;
    for (int j = i + 2; j < i + 8 && j < n; j++) {
      if (j % 2 != i % 2) continue;
      if (s[i] == s[j] && s[i] == s[(i + j) / 2]) {
        indx = j;
        break;
      }
    }
    a[i] = indx;
  }
  for (int i = 0; i < n; i++) {
    long long indx = -1;
    for (int j = i; j < i + 8 && j < n; j++) {
      if (a[j] != -1 && a[j] < i + 8) {
        if (indx == -1)
          indx = a[j];
        else
          indx = min(indx, a[j]);
      }
    }
    if (indx != -1) cnt += max(min(7ll, n - 1 - i) + i - indx + 1, 0ll);
    cnt += max(0ll, n - 1 - i - 8 + 1);
  }
  cout << cnt;
}
