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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 7 |
| 4 | 11 |
| 5 | 21 |
| 6 | 37 |
| 7 | 67 |
| 8 | 121 |
| 9 | 221 |
| 10 | 402 |
| 11 | 731 |
| 12 | 1331 |
| 13 | 2424 |
| 14 | 4415 |
| 15 | 8040 |
| 16 | 14641 |
| 17 | 26664 |
| 18 | 48559 |
| 19 | 88434 |
| 20 | 161051 |
| 21 | 293300 |
| 22 | 534146 |
| 23 | 972766 |
| 24 | 1771561 |
| 25 | 3226297 |
| 26 | 5875604 |
| 27 | 10700416 |
| 28 | 19487171 |
| 29 | 35489262 |
| 30 | 64631635 |
| 31 | 117704566 |
[1,2,4,7,11,21,37,67,121,221,402,731,1331,2424, 4415,8040,14641,26664,48559,88434,161051,293300, 534146,972766,1771561,3226297,5875604,10700416, 19487171,35489262,64631635,117704566] |