import math
m=int(input())
for i in range(0,m):
s=int(input())
pro=1
big=0
li= input().split()
li=[int(u) for u in li]
for l in range(0,s):
pro*=li[l]
pro+=1
for j in range(2,int(math.sqrt(pro))+1):
if pro%j==0:
big=pro//j
break
if big==0:
big=pro
print("Case #",i,":",big)
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