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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 4 |
| 6 | 6 |
| 7 | 9 |
| 8 | 14 |
| 9 | 21 |
| 10 | 32 |
| 11 | 49 |
| 12 | 75 |
| 13 | 115 |
| 14 | 177 |
| 15 | 271 |
| 16 | 416 |
| 17 | 638 |
| 18 | 980 |
| 19 | 1504 |
| 20 | 2309 |
| 21 | 3544 |
| 22 | 5440 |
| 23 | 8351 |
| 24 | 12819 |
| 25 | 19678 |
| 26 | 30207 |
| 27 | 46370 |
| 28 | 71182 |
| 29 | 109269 |
| 30 | 167737 |
| 31 | 257489 |
| 32 | 395265 |
| 33 | 606763 |
| 34 | 931428 |
| 35 | 1429814 |
| 36 | 2194875 |
| 37 | 3369304 |
| 38 | 5172143 |
| 39 | 7939641 |
[2,1,2,3,4,6,9,14,21,32,49,75,115,177,271,416,638, 980,1504,2309,3544,5440,8351,12819,19678,30207, 46370,71182,109269,167737,257489,395265,606763, 931428,1429814,2194875,3369304,5172143,7939641] |