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#include "stdio.h"
#define max(a, b) (a > b ? a : b)
int data[200001];
int pre[200001], post[200001];

int gcd(int a, int b) {
    if (b == 0) return a;
    return gcd(b, a%b);
}

int main() {
    int n;
    scanf("%d", &n);
    for (int i = 0; i < n; i++)
        scanf("%d", &data[i]);

    pre[0] = data[0], post[n-1] = data[n-1];
    for (int i = 1; i < n; i++) {
        pre[i] = gcd(pre[i-1], data[i]);
        post[n-i-1] = gcd(post[n-i], data[n-i-1]);
    }

    int ans = max(pre[n-2], post[1]); // Boundary cases
    for (int i = 0; i < n-2; i++)
        ans = max(ans, gcd(pre[i], post[i+2]));
        
    printf("%d\n", ans);

    return 0;
}