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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 15 |
| 5 | 26 |
| 6 | 45 |
| 7 | 75 |
| 8 | 121 |
| 9 | 193 |
| 10 | 302 |
| 11 | 463 |
| 12 | 703 |
| 13 | 1052 |
| 14 | 1555 |
| 15 | 2277 |
| 16 | 3301 |
| 17 | 4740 |
| 18 | 6754 |
| 19 | 9548 |
| 20 | 13398 |
| 21 | 18678 |
| 22 | 25873 |
| 23 | 35620 |
| 24 | 48771 |
| 25 | 66418 |
| 26 | 89988 |
| 27 | 121345 |
| 28 | 162878 |
| 29 | 217666 |
| 30 | 289685 |
| 31 | 383994 |
| 32 | 507059 |
| 33 | 667131 |
| 34 | 874656 |
| 35 | 1142860 |
| 36 | 1488484 |
| 37 | 1932575 |
| 38 | 2501599 |
| 39 | 3228787 |
[0,2,4,8,15,26,45,75,121,193,302,463,703,1052, 1555,2277,3301,4740,6754,9548,13398,18678,25873, 35620,48771,66418,89988,121345,162878,217666, 289685,383994,507059,667131,874656,1142860, 1488484,1932575,2501599,3228787] |