n

1

3

5

7

9

11

13

15

17

19

21

23

25

27

a[n]

1.

−2.3482

1.3617

−1.4977

1.1270

−1.0472

0.8581

−0.7593

0.6390

−0.5568

0.4727

−0.4099

0.3489

−0.3021