Answer:
a(30) = 97
Explanation:
Notice how each new term is equal to the previous term, less 4. So this is a decreasing arithmetic sequence with common difference -4 and first term 213:
The general a(n) = a(1) - 4(n - 1) becomes
a(30) = 213 - 4(30 - 1), or
a(30) = 97