#include <bits/stdc++.h>
int main() {
  long long int i, n, k, arr[2 * 100005], ans[2 * 100005],
      l = 2, sum = 0, last = 0, len, var = 0, m, h = 0, flag = 1;
  scanf("%I64d%I64d", &n, &k);
  len = n;
  for (i = 1; i <= n; ++i) scanf("%I64d", &arr[i]);
  for (i = 2; i < n, l <= n; ++i) {
    if (flag) sum += (i - 2) * arr[l - 1];
    var = (len - i) * (i - 1) * arr[l];
    m = sum - var;
    if (m < k) {
      --i;
      ans[h++] = l;
      ++l;
      len--;
      flag = 0;
    } else {
      ++l;
      flag = 1;
    }
    last = var;
  }
  for (i = 0; i < h; ++i) printf("%I64d\n", ans[i]);
  return 0;
}
