#include <bits/stdc++.h>
using namespace std;

string N;
int p;

long long dp[21][2][2][4][2];

long long dfs(long long i=0, bool tight=true ,bool lz=true, long long sum=0, bool th=false)
{
  long long &ret = dp[i][tight][lz][sum][th];

  if (ret != -1) return ret;
  if (i == N.size()){
    if (lz) return 0;
    return (sum == 0 | th);
  }

  int x = N[i] - '0';
  int r = (tight ? x : 9);
  ret = 0;
  for (int j = 0; j <= r; ++j){
    ret += dfs(i + 1, tight && j == x, lz && j == 0, (sum + j) % 3, th || j == 3);
  }

  return ret;
}
int main()
{
  memset(dp, -1, sizeof(dp));

  cin >> p;
  N = "1";
  for (int i = 0; i < p; i++) N += '0';

  cout << dfs() << endl;
}