/**
 *  Circle and Points (PKU 1981)
 *  by Kenji Inoue, 2007-01-05
 **/

#include <iostream>
#include <complex>

using namespace std;

typedef complex<double> P;

#define EPS (1e-6)

P p[300];
P tmp;

int main() {
  int n;
  while (cin >> n, n) {
    for (int i=0; i<n; i++) {
      cin >> p[i].real() >> p[i].imag();
    }

    int ans = 1;
    for (int i=0; i<n; i++) {
      for (int j=i+1; j<n; j++) {
        P v = p[i] - p[j];
        double absv = abs(v);
        if (absv > 2.0 + EPS) { continue; }

        P m = p[j] + (v / 2.0);
        P unv = (v * P(0, 1)) / absv; // unit normal vector
        P nv = sqrt(1.0 - absv*absv/4.0) * unv;
        for (int s=0; s<2; s++) {
          nv *= -1;
          P c = m + nv; // center point of the circle

          int cnt = 0;
          for (int k=0; k<n; k++) {
            // if (abs(p[k] - c) < 1.0 + EPS) { cnt++; } // too slow
            tmp = p[k] - c;
            if ( tmp.real()*tmp.real() + tmp.imag()*tmp.imag() < 1.0 + EPS ) { cnt++; }
          }
          if (cnt > ans) { ans = cnt; }
        }
      }
    }

    cout << ans << endl;
  }

  return 0;
}