#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 1;
int n, m;
int dp[N][18], lvl[N];
int lca(int a, int b) {
  if (lvl[a] < lvl[b]) swap(a, b);
  for (int i = 17; i >= 0; i--)
    if (lvl[dp[a][i]] >= lvl[b]) a = dp[a][i];
  if (a == b) return a;
  for (int i = 17; i >= 0; i--)
    if (dp[a][i] != dp[b][i]) a = dp[a][i], b = dp[b][i];
  if (a == b) return a;
  return dp[a][0];
}
int dist(int a, int b) { return lvl[a] + lvl[b] - 2 * lvl[lca(a, b)]; }
int main() {
  scanf("%d", &n);
  int p;
  int a = 0, b = 0;
  int best = 0;
  for (int i = 1; i < n; i++) {
    scanf("%d", &p);
    --p;
    lvl[i] = lvl[p] + 1;
    dp[i][0] = p;
    for (int j = 1; (1 << j) <= lvl[i]; j++) dp[i][j] = dp[dp[i][j - 1]][j - 1];
    if (a == p)
      a = i, ++best;
    else if (b == p)
      b = i, ++best;
    else {
      int da = dist(a, i), db = dist(b, i);
      if (da > best) best = da, b = i;
      if (db > best) best = db, a = i;
    }
    printf("%d ", best);
  }
  putchar('\n');
  return 0;
}
