n = int(input())
maxnod = 1
nods = [0] * 100
for i in range(n):
   a = int(input())
   for i in range(a//2):
      if a % (i + 1) == 0:
         nods[i + 1] += 1
         nods[a//(i + 1)] += 1
         if nods[a//(i + 1)] > 1 and a//(i + 1) > maxnod:
            maxnod = a//(i + 1)
         elif nods[i + 1] > 1 and i + 1 > maxnod:
            maxnod = i + 1
print(maxnod)