Answer
See below.
Work Step by Step
As we can see, $a_1=3$, and each term is $4$ times more than the previous one. Thus $a_n=4a_{n-1}$ is the recursive rule.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.