#include<iostream>
#include<vector>
#include<cmath>
#include<set>
#include<string>
#include<sstream>
#include <bits/stdc++.h>
#include "BigIntegerLibrary.hh"

using namespace std;

vector <bool> v;
vector <unsigned long long int> primers;
vector <vector <unsigned long long int> > factors;
vector <vector <unsigned long long int> > factorsrepet;
vector <vector <BigInteger> > bino;

string int2string(int n){
    stringstream s;
    s << n;
    return(s.str());
}

void garbell(){
    v[0]=false;
    v[1]=false;
    factors[0].push_back(0);
    factors[1].push_back(1);
    for(unsigned long long int i=2; i<v.size(); i++){
        if(v[i]){
            primers.push_back(i);
            factors[i].push_back(i);
            for(unsigned long long int h=2; h*i<v.size(); h++){
                v[i*h] = 0;
                factors[i*h].push_back(i);
            }
        }
    }
}

int main(){
    int n;
    cin >> n;
    v = vector <bool> (n, true);
    primers = vector <unsigned long long int> ();
    factors = vector <vector <unsigned long long int>> (n);
    factorsrepet = vector <vector <unsigned long long int>> (n);
    garbell();
    bino = vector <vector <BigInteger> > (n);
    bino[0].push_back(1);
    bino[1].push_back(1);
    bino[1].push_back(1);
    for(unsigned long long int i=2; i<n; i++) {
        //cout<<endl<<endl<<1<<"  ";
        bino[i].push_back(1);
        for(unsigned long long int j=1; j<i; j++){
            bino[i].push_back(bino[i-1][j-1]+bino[i-1][j]);
            //cout<<bino[i][j]<<"  ";
        }
        bino[i].push_back(1);
    }
    for(unsigned long long int i=2; i<n; i++) {
        cout<<"n =      "<<i;
        unsigned long long int aa = 0;
        unsigned long long int bb = 1;
        unsigned long long int p1 = primers[aa];
        unsigned long long int p2 = primers[bb];
        unsigned long long int res = 0;
        int howmany = 0;
        while(res==0){
                string pp1 = int2string(p1);
                BigInteger ppp1 =stringToBigInteger(pp1);
                string pp2= int2string(p2);
                BigInteger ppp2 =stringToBigInteger(pp2);
                for(unsigned long long int q=1; q<=i/2; q++){
                        if((bino[i][q]%ppp1!=0)and(bino[i][q]%ppp2!=0)){
                            res = 1;
                            break;
                    }
                }
            if(res==0){
                cout<<endl<<"PRIMES: "<<ppp1<<"  "<<ppp2;
                howmany++;
            }
            if(((bb+1==primers.size())and(aa+1==primers.size()-1))or(primers[aa+1]==i)){
                    res=1;
               }
               else{
               if((bb+1==primers.size())or(primers[bb+1]>i)){
                    aa++;
                    p1 = primers[aa];
                    bb = aa+1;
                    p2 = primers[bb];
                    res = 0;
                }
                else{
                    bb++;
                    p2 = primers[bb];
                    res = 0;
                }
            }
   }
   cout<<endl<<"  number of pairs: "<<howmany<<endl<<endl;
    }
}