#include <bits/stdc++.h>
using namespace std;
const long long inf = 1e9;
const long long maxn = 3e5 + 10;
char s[maxn];
long long pos[maxn];
long long read() {
  long long x = 0, f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    x = x * 10 + ch - '0';
    ch = getchar();
  }
  return x * f;
}
void print(long long x) {
  if (x < 0) putchar('-'), x = -x;
  if (x > 9) print(x / 10);
  putchar(x % 10 + '0');
}
void write(long long x) {
  print(x);
  puts("");
}
signed main() {
  scanf("%s", s + 1);
  long long n = strlen(s + 1), ans = 0;
  for (long long i = 0; i < maxn; i++) pos[i] = inf;
  for (long long i = 1; i <= n; i++)
    for (long long j = 1; i + 2 * j <= n; j++)
      if (s[i] == s[i + j] && s[i] == s[i + 2 * j]) {
        pos[i] = i + 2 * j;
        break;
      }
  for (long long i = n; i >= 1; i--) pos[i] = min(pos[i], pos[i + 1]);
  for (long long i = 1; i <= n; i++)
    if (pos[i] != inf) ans += n - pos[i] + 1;
  write(ans);
  return 0;
}
