A recursion formula and the initial term(s) of a sequence are given. Write out the first five terms of the sequence.
-$$a _ { 1 } = 1 , a _ { n + 1 } = 5 a _ { n }$$
A) 1, 5, 25, 125, 625
B) 1, 6, 11, 16, 21
C) 5, 6, 7, 8, 9
D) 5, 25, 125, 625, 3125

Question

Quizplus · Accepted Answer

The given recursion formula is $a_{n+1} = 5a_n$ with the initial term $a_1 = 1$. Applying the formula: $a_2 = 5 \cdot 1 = 5$, $a_3 = 5 \cdot 5 = 25$, $a_4 = 5 \cdot 25 = 125$, $a_5 = 5 \cdot 125 = 625$.

A Recursion Formula and the Initial Term(s) of a Sequence a1=1,an+1=5ana _ { 1 } = 1 , a _ { n + 1 } = 5 a _ { n }a1​=1,an+1​=5an​

A Recursion Formula and the Initial Term(s) of a Sequence $a _ { 1 } = 1 , a _ { n + 1 } = 5 a _ { n }$