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

#define int long long

typedef long long ll;
typedef pair<int,int>pint;
typedef vector<int>vint;
typedef vector<pint>vpint;
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define ln <<endl
#define all(v) (v).begin(),(v).end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define reps(i,f,n) for(int i=(f);i<(n);i++)
#define each(it,v) for(__typeof((v).begin()) it=(v).begin();it!=(v).end();it++)
template<class T,class U>void chmin(T &t,U f){if(t>f)t=f;}
template<class T,class U>void chmax(T &t,U f){if(t<f)t=f;}

int memo[50][3];

int dfs(int p,int m){
    int &ret=memo[p][m];
    if(ret!=-1)return ret;
    if(p==0){
        return m!=0;
    }
    ret=0;
    for(int i=0;i<10;i++){
        if(i==3)continue;
        ret+=dfs(p-1,(m+i)%3);
    }
    return ret;
}

signed main(){
    int P;cin>>P;
    memset(memo,-1,sizeof(memo));
    int tmp=dfs(P,0);
    int L=1;rep(i,P)L*=10;L--;
    cout<<L-tmp<<endl;
    return 0;
}