Answer: Option B.
Explanation:
A recursive formula is written as:
aₙ = aₙ₋₁*13
Now, if the first term is 7, then:
a₁ = 7
This means that:
a₂ = 7*13
a₃ = (7*13)*13 = 7*(13)^2
a₄ = (7*13^2)*13 = 7*(13)^3
You already can see the pattern here, the n-th term will be written as:
aₙ = 7*(13)^(n - 1)
Then the correct option is B