#include <bits/stdc++.h>
using namespace std;
int n, k, res, tmp, m;
vector<int> v;
bool check(int val) {
  int m = n - val;
  return m % (2 * k + 1) <= k;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  cin >> n >> k;
  int i = min(n, k + 1);
  while (!check(i)) i--;
  while (i <= n) {
    if (i <= n) v.push_back(i);
    i += 2 * k + 1;
  }
  if (v[v.size() - 1] + k < n) v.push_back(n);
  cout << v.size() << "\n";
  for (int i = 0; i < v.size(); i++) cout << v[i] << " ";
  return 0;
}
