Answer:
13+6(n-2)
Explanation:
Considering that the second term is 13 and that the term to term rule is add 6, your expression would be 13 plus the result of multiplying 6 for the number in the sequence minus 2 because you already have the second term, so you don't have to count the first two terms in this part of the expression:
13+6(n-2)