#include <bits/stdc++.h>
using namespace std;
long long A, tot, Now, step;
int x, n, k;
int main() {
  scanf("%d %d", &n, &k);
  Now = n;
  step = 0;
  for (int i = 1; i <= n; ++i) {
    scanf("%d", &x);
    A = tot - (long long)(Now - step - 1) * x * step;
    if (A < k)
      printf("%d\n", i), --Now;
    else
      tot += (long long)x * step, ++step;
  }
}
