#include <stdio.h>
#include <string>
#include <cstring>
#include <stdlib.h>
#include <math.h>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <list>
#include <iterator>
#include <assert.h>
#pragma warning(disable:4996) 

typedef long long ll;
#define MIN(a, b) ((a)>(b)? (b): (a))
#define MAX(a, b) ((a)<(b)? (b): (a))
#define LINF 9223300000000000000
#define INF 2140000000
const long long MOD = 1000000007;
//const long long MOD = 998244353;

using namespace std;


vector<int> pp;
void preparePrime( int maxp )
{
    int i;
    vector<int> a(maxp+1);
    for(i=2; i<=maxp; i++) {
        int k=i+i;
        while(k<=maxp) {
            a[k]=1;
            k+=i;
        }
    }
    for(i=2; i<=maxp; i++) {
        if(a[i]==0) pp.push_back( i );
    }
    return;
}

void solve()
{
    int n;
    scanf("%d", &n);
    preparePrime( (int)sqrt((double)n)+1 );

    vector<int> a(n), ans(n,1);
    int i;
    for(i=1; i<n; i++) {
        a[i]=i;
    }
    for(i=0; i<(int)pp.size(); i++) {
        int curr=pp[i];        
        while(curr<n) {
            int cnt=0;
            while(a[curr]%pp[i]==0) {
                a[curr]/=pp[i];
                cnt++;
            }
            if(cnt) {
                ans[curr]*=(cnt+1);
            }
            curr+=pp[i];
        }
    }

    for (i = 1; i < n; i++) {
        if(a[i]>1) {
            ans[i]*=2;
        }
    }
    ans[1]=1;

    vector<pair<int, pair<int,int> > > z;
    for(i=1; i<n; i++) {
        int j=n-i;
        int tmp=abs((i-ans[i])-(j-ans[j]));
        z.push_back(make_pair(tmp,make_pair(i,j)));
    }
    sort(z.begin(),z.end());

    int save;
    for(i=0; i<n-1; i++) {
        if(i==0) save=z[i].first;
        else {
            if(z[i].first!=save) break;
        }
        printf("%d %d\n", z[i].second.first, z[i].second.second);
    }

    return;
}


int main(int argc, char* argv[])
{
#if 1
	solve();
#else
	int T; scanf("%d", &T);
	while (T--) {
		solve();
	}
#endif
	return 0;
}