#include <iostream>
#include <iomanip>
#include <sstream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <climits>
#include <cfloat>
#include <vector>
#include <string>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <algorithm>
#include <functional>
#include <utility>
#include <numeric>
#include <iterator>

using namespace std;

typedef long long LL;
typedef unsigned long long ULL;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int,int> PII;
typedef vector<PII> VPII;
typedef istringstream ISS;
typedef ostringstream OSS;

#define REP( i, m, n ) for ( int i = (int)( m ); i < (int)( n ); ++i )
#define FOR( v, c ) for ( auto &v : c )
#define EACH( it, c ) for ( auto it = c.begin(); it != c.end(); ++it )
#define ALL( c ) (c).begin(), (c).end()
#define DRANGE( c, p ) (c).begin(), (c).begin() + p, (c).end()

#define PB( n ) push_back( n )
#define MP( a, b ) make_pair( ( a ), ( b ) )
#define EXIST( c, e ) ( (c).find( e ) != (c).end() )

#define fst first
#define snd second

#define DUMP( x ) cerr << #x << " = " << ( x ) << endl
#define DEBUG( x ) cerr << __FILE__ << ":" << __LINE__ << ": " << #x << " = " << ( x ) << endl

#include <complex>
typedef complex<double> Point;
const double EPS = 1e-8;

// テ・ツ?・テ・ツ環崚」ツつケテ」ツδ暗」ツδェテ」ツδシテ」ツδ?」ツ?凝」ツつ嘉・ツョツ淌ヲツ閉ーテ、ツコツ古」ツ?、テ」ツつ津」ツ?ィテ」ツ?」テ」ツ?ヲ Point テ」ツ?ク
istream& operator >> ( istream &s, Point &a )
{
	double r, i;
	s >> r >> i;
	a = Point( r, i );
	return s;
}

// テ・ツ債佚、ツスツ催」ツδ凖」ツつッテ」ツδ暗」ツδォ
Point unitVector( const Point &a )
{
	return a / abs( a );
}

// テヲツウツ陛ァツキツ堙」ツδ凖」ツつッテ」ツδ暗」ツδォ
Point normalVector1( const Point &a )
{
	return a * Point( 0, 1 );
}
Point normalVector2( const Point &a )
{
	return a * Point( 0, -1 );
}
Point ( *normalVectors[] )( const Point& ) = { normalVector1, normalVector2 };

int main()
{
	cin.tie( 0 );
	ios::sync_with_stdio( false );

	for ( int n; cin >> n, n; )
	{
		vector<Point> ps( n );
		FOR( p, ps )
		{
			cin >> p;
		}

		int res = 0;
		REP( i, 0, n )
		{
			REP( j, 0, i )
			{
				const Point &a = ps[i], &b = ps[j];
				REP( k, 0, 2 )
				{
					const Point c = ( a + b ) / Point( 2, 0 ) + unitVector( normalVectors[k]( a - b ) ) * sqrt( 1 - pow( abs( a - b ) / 2., 2. ) );

					int tmp = 2;
					REP( l, 0, n )
					{
						if ( l == i || l == j )
						{
							continue;
						}

						tmp += abs( c - ps[l] ) <= 1 + EPS;
					}
					res = max( res, tmp );
				}
			}
		}
		cout << res << endl;
	}

	return 0;
}