h(n) = -17·0.2^(n-1)
Explanation:
The explicit formula for a geometric sequence with first term a1 and common ratio r is ...
an = a1·r^(n-1)
Your sequence h has first term a1 = -17 and common ratio r = 0.2. Then the explicit formula is ...
h(n) = -17·0.2^(n-1)