There are N integers, A_1, A_2, ..., A_N, written on the blackboard.
You will choose one of them and replace it with an integer of your choice between 1 and 10^9 (inclusive), possibly the same as the integer originally written.
Find the maximum possible greatest common divisor of the N integers on the blackboard after your move.

-----Constraints-----
- All values in input are integers.
- $2 \leq N \leq 10^5$
- $1 \leq A_i \leq 10^9$

-----Output-----
Input is given from Standard Input in the following format:
N
A_1 A_2 ... A_N

-----Output-----
Print the maximum possible greatest common divisor of the N integers on the blackboard after your move.

-----Sample Input-----
3
7 6 8

-----Sample Output-----
2

If we replace 7 with 4, the greatest common divisor of the three integers on the blackboard will be 2, which is the maximum possible value.

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