// 2004�‘“à—\‘ID Circle and Points

#include <iostream>
#include <queue>
#include <cmath>

using namespace std;

const double sqrt2 = sqrt(2.0); 
const double eps = 1e-6;
char dx[] = {-1,1,-1,1};
char dy[] = {1,1,-1,-1};

class Square{
public:
	int bound; double x, y, size;
	Square(int bound, double x, double y, double size) : bound(bound), x(x), y(y), size(size) {}
	bool operator < (const Square &s) const { return bound < s.bound; }
};

inline double sqr(double x) { return x*x; }

int main(){
	int N;
	double x[300], y[300];
	while(cin >> N){
		if(!N) break;
		for(int i=0;i<N;i++) cin >> x[i] >> y[i];
		int ans = 1;
		priority_queue<Square> qu;
		qu.push(Square(N, 5.0, 5.0, 10.0));
		while(!qu.empty()){
			Square s = qu.top(); qu.pop();
			if(s.bound <= ans) break;
			for(int i=0;i<4;i++){
				double nx = s.x + dx[i]*s.size/2.0;
				double ny = s.y + dy[i]*s.size/2.0;
				int c = 0, upper = 0;
				for(int j=0;j<N;j++){
					double dist = sqr(x[j]-nx)+sqr(y[j]-ny);
					if(dist < 1.0+eps) c++;
					if(dist < sqr(1.0+sqrt2*s.size/2.0)+eps) upper++;
				}
				ans = max(ans, c);
				if(upper > ans) qu.push(Square(upper, nx, ny, s.size/2.0));
			}
		}
		cout << ans << endl;
	}
}