#include <bits/stdc++.h>   using namespace std;   pair<int, int> h[100010], h1[100010];   long long cnt[100010], pre[100010], sum[100010];   int num[100010], mx[100010], n, tt, t1;   inline int rd() {     int x = 0;     char ch = getchar();     for (; ch <  0  || ch >  9 ; ch = getchar())       ;     for (; ch >=  0  && ch <=  9 ; ch = getchar()) x = x * 10 + ch -  0 ;     return x;   }   inline int gcd(int x, int y) { return (!y) ? x : gcd(y, x % y); }   inline long long calc(long long l, long long r) {     return (l + r) * (r - l + 1) / 2;   }   inline long long anol_gcd(long long n, long long a, long long b, long long c) {     if (n < 0) return 0;     if (!a) return (b / c) * (n + 1);     if (a >= c || b >= c)       return (a / c) * n * (n + 1) / 2 + (b / c) * (n + 1) +              anol_gcd(n, a % c, b % c, c);     long long hh = (a * n + b) / c;     return n * hh - anol_gcd(hh - 1, c, c - b - 1, a);   }   inline long long gao(int x, int y, long long mid) {     if (!cnt[x] || !cnt[y]) return 0;     mid -= pre[y - 1] - pre[x];     if (mid < 0) return 0;     long long mn = (mid - cnt[y] * y) / x;     mn = max(mn, 0LL);     if (mn >= cnt[x]) return cnt[x] * cnt[y];     long long res = mn * cnt[y];     mn++;     long long mx = mid / x;     mx = min(mx, cnt[x]);     if (mn <= mx) res += anol_gcd(mx - mn, x, mid - mx * x, y);     return res;   }   inline long long check(long long mid) {     long long res = 0;     int now = 1;     for (int i = 1; i <= 100000; i++) {       now = max(now, i);       long long hh = min(mid / i, cnt[i]);       if (cnt[i]) res += calc(cnt[i] - hh + 1, cnt[i]);       while (now + 1 <= 100000 && pre[now + 1] - pre[i - 1] <= mid) now++;       res += (sum[now] - sum[i]) * cnt[i];       mx[i] = now;     }     for (int i = 1; i <= 100000; i++)       for (int j = mx[i] + 1; j <= min(mx[i + 1] + 1, 100000); j++)         res += gao(i, j, mid);     return res;   }   int main() {     n = rd();     for (int i = 1; i <= n; i++) num[i] = rd();     cnt[num[1]]++;     h[tt = 1] = pair<int, int>(1, num[1]);     for (int i = 2; i <= n; i++) {       t1 = tt;       for (int j = 1; j <= t1; j++)         h1[j] = h[j], h1[j].second = gcd(h1[j].second, num[i]);       h1[++t1] = pair<int, int>(1, num[i]);       tt = 0;       for (int j = 1; j <= t1;) {         int k = j, now = 0;         for (; k <= t1 && h1[k].second == h1[j].second; k++) now += h1[k].first;         h[++tt] = pair<int, int>(now, h1[j].second);         j = k;       }       for (int j = 1; j <= tt; j++) cnt[h[j].second] += h[j].first;     }     for (int i = 1; i <= 100000; i++)       pre[i] = pre[i - 1] + cnt[i] * i, sum[i] = sum[i - 1] + cnt[i];     long long all = (long long)n * (n + 1) / 2;     all = all * (all + 1) / 2;     all = (all + 1) / 2;     long long l = 0, r = (long long)n * (n + 1) / 2 * 100000;     while (l < r) {       long long mid = (l + r) >> 1;       if (check(mid) >= all)         r = mid;       else         l = mid + 1;     }     printf( %lld n , l);     return 0;   }   