Question
What are the missing numbers?
8161, 8171, (a)         , 8191, (b)         , 8211
2 m
(a)

Click button first when a symbol is required. X

(b)

Click button first when a symbol is required. X

What are the missing numbers?
8161, 8171, (a)         , 8191, (b)         , 8211