Problem

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Tags: algebra



In the following sequence of numbers, each term, starting with the third, is obtained by adding three times the previous term plus twice the previous term to the previous one: $$a_1, a_2, 78, a_4, a_5, 3438, a_7, a_8,…$$As seen in the sequence, the third term is $78$ and the sixth term is $3438$. What is the value of the term $a_7$?