#include <bits/stdc++.h>
using namespace std;

#define rep(i,n) for(long long i = 0; i < (long long)(n); i++)
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define fi first
#define se second
#define mt make_tuple
template<class T1, class T2> bool chmin(T1 &a, T2 b) { return b < a && (a = b, true); }
template<class T1, class T2> bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); }

using ll = long long; using ld = long double; using vll = vector<ll>; using vvll = vector<vll>; using vld = vector<ld>; 
using vi = vector<int>; using vvi = vector<vi>;
using P = pair<ll, ll>;

template <typename T, typename U> ostream &operator<<(ostream &o, const pair<T, U> &v) {  o << "(" << v.first << ", " << v.second << ")"; return o; }
template<size_t...> struct seq{}; template<size_t N, size_t... Is> struct gen_seq : gen_seq<N-1, N-1, Is...>{}; template<size_t... Is> struct gen_seq<0, Is...> : seq<Is...>{};
template<class Ch, class Tr, class Tuple, size_t... Is>
void print_tuple(basic_ostream<Ch,Tr>& os, Tuple const& t, seq<Is...>){ using s = int[]; (void)s{0, (void(os << (Is == 0? "" : ", ") << get<Is>(t)), 0)...}; }
template<class Ch, class Tr, class... Args> 
auto operator<<(basic_ostream<Ch, Tr>& os, tuple<Args...> const& t) -> basic_ostream<Ch, Tr>& { os << "("; print_tuple(os, t, gen_seq<sizeof...(Args)>()); return os << ")"; }
ostream &operator<<(ostream &o, const vvll &v) { rep(i, v.size()) { rep(j, v[i].size()) o << v[i][j] << " "; cout << endl; } return o; }
template <typename T> ostream &operator<<(ostream &o, const vector<T> &v) { o << '['; rep(i, v.size()) o << v[i] << (i != v.size()-1 ? ", " : ""); o << "]";  return o; }
template <typename T>  ostream &operator<<(ostream &o, const set<T> &m) { o << '['; for (auto it = m.begin(); it != m.end(); it++) o << *it << (next(it) != m.end() ? ", " : ""); o << "]";  return o; }
template <typename T, typename U>  ostream &operator<<(ostream &o, const map<T, U> &m) { o << '['; for (auto it = m.begin(); it != m.end(); it++) o << *it << (next(it) != m.end() ? ", " : ""); o << "]";  return o; }
template <typename T, typename U>  ostream &operator<<(ostream &o, const unordered_map<T, U> &m) { o << '['; for (auto it = m.begin(); it != m.end(); it++) o << *it; o << "]";  return o; }
#define VN(v) # v
#define print(a) cout << a << "#" << VN(a) << endl;
#define ldout fixed << setprecision(40) 

static const double EPS = 1e-14;
static const long long INF = 1e18;
static const long long mo = 1e9+7;

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

    ll n; 
    while (cin >> n && n) {
        vld x(n), y(n); rep(i, n) cin >> x[i] >> y[i];
        auto d = [&](ll i, ll j) { return (x[i] - x[j]) * (x[i] - x[j]) + (y[i] - y[j]) * (y[i] - y[j]); };
        ll ret = 1;
        for (int i = 0; i < n-1; i++) {
            for (int j = i+1; j < n; j++) {
                ld dij = d(i, j);
                if (dij >= 4) continue;
                ld x1 = x[i], y1 = y[i], x0 = x[j], y0 = y[j];
                for (auto dir : {1, -1}) {
                    ld xc = x0 + (x1 - x0) / 2.0l + (-(y1 - y0)) * dir 
                        * sqrtl(1.0l - ((x1 - x0) * (x1 - x0) + (y1 - y0) * (y1 - y0)) / 4.0l) 
                        / sqrtl((y1 - y0) * (y1 - y0)  + (x1 - x0) * (x1 - x0));
                    ld yc = y0 + (y1 - y0) / 2.0l + (+(x1 - x0)) * dir 
                        * sqrtl(1.0l - ((x1 - x0) * (x1 - x0) + (y1 - y0) * (y1 - y0)) / 4.0l) 
                        / sqrtl((y1 - y0) * (y1 - y0)  + (x1 - x0) * (x1 - x0));
//                    cout << x1 << " " << y1 << " " << x0 << " " << y0 << " : " << xc << " " << yc << endl;
                    ll m = 2;
                    rep(k, n) {
                        if (k == i || k == j) continue;
                        if ((xc - x[k]) * (xc - x[k]) + (yc - y[k]) * (yc - y[k]) < 1) 
                            m++;
                    }
                    chmax(ret, m);
                }
            }
        }
        cout << ret << endl;
    }
    return 0;
}

Measured memory_bytes: 3160