#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, k;
  scanf("%d%d", &n, &k);
  int width = 2 * k + 1;
  if (width >= n) {
    printf("1\n");
    printf("%d", n / 2 + n % 2);
    return 0;
  }
  if (n % width == 0) {
    printf("%d\n", n / width);
    for (int out = k + 1; out <= n; out += width) {
      printf("%d ", out);
    }
    return 0;
  }
  vector<int> v;
  for (int i = 1, rest; i <= k; ++i) {
    rest = n - i - k;
    if (rest % width > k || rest % width == 0) {
      for (int out = i; out <= n; out += width) {
        v.push_back(out);
      }
      break;
    }
  }
  printf("%d\n", v.size());
  for (int i = 0; i < v.size(); ++i) {
    printf("%d ", v[i]);
  }
}
