Question

The first 9 terms of a sequence are 8, 7, 5, 1, -7, -23, -55, -119, -247. Which recursive formula could have been used to produce these terms

Answer 1

a₁ = 8

aₙ₊₁ = -2 * aₙ + (n + 1), for n ≥ 1

Explanation:

Starting with the first term (8), multiply by -2: 8 * (-2) = -16.

Then, add a specific value to it: -16 + 9 = -7 (which is the second term).

Repeat this process for each subsequent term.