# Sequence

Calculate what member of the sequence specified by
$\{ 4^{n-2}+85 \}$
has value 86.

Correct result:

n =  2

#### Solution:

$4^{n-2}+85 = 86 \ \\ 4^{n-2} = 1 \ \\ (n-2)\ln(4) = \ln(1) \ \\ n = 2 + \dfrac{ \ln(1)}{ \ln(4)} \ \\ n = 2$

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