--{-# LANGUAGE OverloadedStrings #-}
--{-# LANGUAGE OverloadedLists   #-}
{-# LANGUAGE BangPatterns      #-} --引数に!
{-# LANGUAGE MultiWayIf        #-}
{-# LANGUAGE TupleSections     #-}

import Data.Bits
import Data.Maybe (fromJust)
import Data.List
import qualified Data.Vector.Unboxed as V
import Control.Monad
import qualified Data.ByteString.Lazy.Char8 as B

type Ans = Int

solve :: Int -> [Int] -> Ans
solve n as = maximum $ sub 0
  where
    lgcd = V.fromList $ scanl1 gcd as
    rgcd = V.fromList $ scanr1 gcd as
    sub :: Int -> [Int]
    sub 0 = rgcd V.! 1 : (sub 1)
    sub i | i == n-1 = [lgcd V.! (n-2)]
          | otherwise = gcd (lgcd V.! (i-1)) (rgcd V.! (i+1)) : (sub (i+1))



readBInt :: B.ByteString -> Int
readBInt = fst . fromJust . B.readInt

main0 :: B.ByteString -> Ans
main0 cont =
   let remLines0 = map (map readBInt . B.words) (B.lines cont)
       [n]:remLines1 = remLines0
       as = head remLines1
       in solve n as

main :: IO ()
main = print . main0 =<< B.getContents
