How do you write an nth term rule for $r=1/8$ and $a_1=4$ ?

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Answer 1 · 2017-10-17T13:44:12

$a_n=4(1/8)^(n-1)$

presumably this is a geometric sequence question

in which case
for a GP

$a_1=$ the first term#

$r=$ the common ratio

we ahve

$a_1, a_1r, a_1r^2,...,a_1r^(n-1),..$

in this case we re given

$a_1=4$

$r=1/8$

so $a_n=4(1/8)^(n-1)$

How do you write an nth term rule for r=1/8r=1/8 and a_1=4a_1=4?