Final answer:
The first six terms in the sequence defined by the given recursion formula are 1, -1, -2, 4, -16, -128.
Step-by-step explanation:
To find the first six terms in the sequence defined by the recursion a₁=1, a₂=-1, aₙ+₁=2aₙ₋₃aₙ₋₁, we can use the given formula. We start with the initial terms a₁=1 and a₂=-1. Then, we apply the recursion formula to find the next terms:
- a₃ = 2a₁a₂ = 2(1)(-1) = -2
- a₄ = 2a₂a₃ = 2(-1)(-2) = 4
- a₅ = 2a₃a₄ = 2(-2)(4) = -16
- a₆ = 2a₄a₅ = 2(4)(-16) = -128
Therefore, the first six terms in the sequence are 1, -1, -2, 4, -16, -128.