#include <iostream>
#include <sstream>
#include <string>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <algorithm>
#include <cstdio>
#include <cmath>
#include <complex>

using namespace std;

#define all(c) ((c).begin()),((c).end())
#define debug(c) cerr<<"> "<<#c<<" = "<<(c)<<endl;
#define iter(c) __typeof((c).begin())
#define tr(i,c) for(iter(c) i=(c).begin();i!=(c).end();i++)
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define REP(i,a,b) for(int i=(int)(a);i<=(int)(b);i++)

#define mp make_pair
#define fst first
#define snd second
#define pb push_back

typedef long long ll;
typedef vector<int> vi;
typedef pair<int,int> pii;

#define EPS 1.0e-6

//ツ点
typedef complex<double> P;

struct C{
	P p;
	double r;
};

vector<P> isCC(const C &c1, const C &c2) {
	double d = abs(c1.p - c2.p);
	if (c1.r + c2.r - d < -EPS || fabs(c1.r - c2.r) - d > EPS) return vector<P>();
	double x = (d*d + c1.r * c1.r - c2.r * c2.r) / 2 / d;
	double y = sqrt(c1.r * c1.r - x * x);
	P diff = (c2.p - c1.p) / d;
	vector<P> res;
	res.pb(c1.p + diff * P(x, y));
	if (y != 0) res.pb(c1.p + diff * P(x, -y));
	return res;
}


int main() {
	for (int N; cin >> N, N != 0; ) {
		vector<P> ps;
		rep (i, N) {
			double x, y; cin >> x >> y;
			ps.pb(P(x, y));
		}
		int res = 0;
		rep (i, N) REP (j, i + 1, N-1) {
			vector<P> isp = isCC((C){ps[i],1},(C){ps[j],1});
			rep (k, isp.size()) {
				int cnt = 0;
				rep (l, N) if (abs(isp[k] - ps[l]) <= 1 + EPS) cnt++;
				res = max(res, cnt);
			}
		}
		if (res == 0) res++;
		cout << res <<endl;
	}
	
	return 0;
}