#include <iostream>
#include <cstdio>
#include <iomanip>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <bitset>
#include <stack>
#include <utility>
#include <numeric>
#include <algorithm>
#include <functional>
#include <cctype>
#include <complex>
#include <string>
#include <sstream>
#include <fstream>
#include <cassert>
using namespace std;

//common

typedef int  i32;
typedef long long i64,ll;
typedef long double ld;

#define BR "\n"
#define ALL(c) (c).begin(),(c).end()
#define REP(i,n) for(int i=0;i<(int)(n);++i)
#define FOR(i,l,r) for(int i=(int)l;i<(int)(r);++i)
#define EACH(it,o) for(auto it = (o).begin(); it != (o).end(); ++it)
#define IN(l,v,r) ((l)<=(v) && (v)<(r))

//config
//#define NDEBUG
//#define INF 1<<30
//#define EPS 1e-8
//const ll MOD =100000007;

//debug
#ifdef NDEBUG
#define DUMP(x)
#define DUMPLN(x)
#define DEBUG(x)
#define DEBUGLN(x)
#define LINE()
#define LINELN()
#define CHECK(exp,act)
#define STOP(e)
#else
#define DUMP(x)  cerr << #x << " = " << (x)
#define DUMPLN(x)  DUMP(x) <<endl
#define DEBUG(x) DUMP(x) << LINE() << " " << __FILE__
#define DEBUGLN(x) DEBUG(x)<<endl
#define LINE()    cerr<< " (L" << __LINE__ << ")"
#define LINELN()    LINE()<<endl
#define CHECK(exp,act)  if(exp!=act){DUMPLN(exp);DEBUGLN(act);}
#define STOP(e)  CHECK(e,true);if(!(e)) exit(1);
#endif

template<class T> inline string toString(const vector<T>& x) {
	stringstream ss;
	REP(i,x.size()){
		if(i!=0)ss<<" ";
		ss<< x[i];
	}
	return ss.str();
}

template<class T> inline string toString(const vector<vector<T> >& map) {
	stringstream ss;
	REP(i,map.size()){
		if(i!=0)ss<<BR;
		ss<< toString(map[i]);
	}
	return ss.str();
}
template<class K,class V>  string toString(map<K,V>& x) {
	string res;stringstream ss;
	for(auto& p:x)ss<< p.first<<":" << p.second<<" ";
	return ss.str();
}

string BITtoString(int bit){
    stringstream ss;
    while(bit!=0){ss<<(bit%2);bit/=2;}
    string res=ss.str();reverse(ALL(res));
    return res;
}

template<typename T,typename V> inline T pmod(T v,V MOD){
	return (v%MOD+MOD)%MOD;
}
#define nextInt(n) scanf("%d",&n)
#define defInt(n) int n;nextInt(n)
#define nextLong(n) scanf("%lld",&n)
#define defLong(n) ll n;nextLong(n)
#define nextDouble(n) scanf("%lf",&n)

namespace Ps{
	const double EPS = 1e-8;
	const double INF = 1e12;

	typedef complex<double> P;
	#define X(a) (real(a))
	#define Y(a) (imag(a))
	
	// a×b
	double cross(const P& a,const P& b){
		return imag(conj(a)*b);
	}
	// a・b
	double dot(const P&a,const P& b) {
		return real(conj(a)*b);
	}

	 int ccw(const P& a,P b,P c){
		b -= a; c -= a;
		  if (cross(b,c) > 0)   return +1;       // counter clockwise
		  if (cross(b,c) < 0)   return -1;       // clockwise
		  if (dot(b,c) < 0)     return +2;       // c--a--b on line
		  if (norm(b) < norm(c)) return -2;       // a--b--c on line
		  return 0;
	  }

	  double pfmod(double v,double MOD){
		return fmod(fmod(v,MOD)+MOD,MOD);
	 }
	  double AbsArg(double a){
	  	double ret=pfmod(max(a,-a),2*M_PI);
	  	return min(ret,2*M_PI-ret);
	 }

}
using namespace Ps;



class Main{
	public:

	int N;
	vector<P> ps;
	void run(){
		// ifstream cin("D2");
//		ofstream cout( "D2.out" );
		
		while(true){
			cin >> N;if(N==0)break;
			ps=vector<P>(N);
			REP(i,N){
				double x,y;cin >> x >> y;
				ps[i]=P(x,y);
			} 
			int Mv=1;
			REP(i,N)REP(j,N)if(i!=j){//二点選んで距離1の点を取る
				P dir=(ps[i]-ps[j])*0.5;
				dir*=P(cos(M_PI/2),sin(M_PI/2));
				if(abs(dir)>1)continue;
				P m=(ps[i]+ps[j])*0.5;
				P o=m+dir*(sqrt(1-pow(abs(dir),2))/abs(dir));
				
				int v=0;
				REP(k,N)if(abs(ps[k]-o)<=1+EPS)v++;
				

				Mv=max(Mv,v);
			}
			cout << Mv <<endl;
		}
	}


};
int main(){
	cout <<fixed<<setprecision(15);	
	ios::sync_with_stdio(false);
	Main().run();
	return 0;
}

Measured memory_bytes: 1292