2 / 1, - 3 / 2,4 / 3, - 6 / 5,9 / 8. Permutation rule and general term formula

2 / 1, - 3 / 2,4 / 3, - 6 / 5,9 / 8. Permutation rule and general term formula

An = (- 1) ^ (n + 1) multiplied by (n + 1) divided by (1 / √ 5) * {[(1 + √ 5) / 2] ^ (n-1) - [(1 - √ 5) / 2] ^ (n-1)}
N is the number, ^ is the power, divided by is the numerator, followed by the denominator
(1 / √ 5) * {[(1 + √ 5) / 2] ^ (n-1) - [(1 - √ 5) / 2] ^ (n-1)} is similar to the pebonacci sequence. Let's refer to it