#include <bits/stdc++.h>
using namespace std;
int d[212345];
int dx = 1;
int p[18][212345];
int lca(int a, int b) {
  if (d[a] < d[b]) swap(a, b);
  int dff = d[a] - d[b];
  for (int i = 0; i < 18; i++) {
    if ((dff >> i) & 1) a = p[i][a];
  }
  if (a == b) return a;
  for (int i = 17; i >= 0; i--) {
    if (p[i][a] != p[i][b]) {
      a = p[i][a];
      b = p[i][b];
    }
  }
  return p[0][a];
  return a;
}
int len(int a, int b) { return d[a] + d[b] - 2 * d[lca(a, b)]; }
int main() {
  int n;
  cin >> n;
  int a, b;
  d[1] = 1;
  p[0][1] = 1;
  int cr = 1;
  int cl = 2;
  for (int i = 2; i < n + 1; i++) {
    int u;
    cin >> u;
    d[i] = d[u] + 1;
    p[0][i] = u;
    for (int j = 1; j < 18; j++) {
      p[j][i] = p[j - 1][p[j - 1][i]];
    }
    if (i > 2) {
      if (dx < len(cr, i)) {
        dx = len(cr, i);
        cl = i;
      }
      if (dx < len(cl, i)) {
        cr = i;
        dx = len(cl, i);
      }
    }
    cout << dx << " ";
  }
}
