Fill in 4,1, (). 1 / 16,1 / 64 according to the rule

Fill in 4,1, (). 1 / 16,1 / 64 according to the rule

4,1,( 1/4).1/16,1/64.
4=2^2
1=2 ^0
1/16=2^-4
So in () is 2 ^ - 2 = 1 / 4
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