



 
Hi Alynna, I see this as two interwoven sequences, the first being 9, 6, 3, ... Do you see what kind of sequence this is? The second is 4, 8, ... Do you see what kind of sequence this is? Your formula for the $n^{th}$ term $a_n$ is going to say: if $n$ is odd then $a_n = ...$ and if $n$ is even then $a_n = ...$ I hope this helps,  


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