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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 4 |
| 2 | 9 |
| 3 | 28 |
| 4 | 67 |
| 5 | 137 |
| 6 | 260 |
| 7 | 477 |
| 8 | 847 |
| 9 | 1456 |
| 10 | 2459 |
| 11 | 4097 |
| 12 | 6766 |
| 13 | 11103 |
| 14 | 18141 |
| 15 | 29550 |
| 16 | 48033 |
| 17 | 77963 |
| 18 | 126416 |
| 19 | 204841 |
| 20 | 331763 |
| 21 | 537156 |
| 22 | 869519 |
| 23 | 1407325 |
| 24 | 2277546 |
| 25 | 3685654 |
| 26 | 5964070 |
| 27 | 9650654 |
| 28 | 15615716 |
| 29 | 25267426 |
| 30 | 40884264 |
| 31 | 66152880 |
| 32 | 107038404 |
| 33 | 173192616 |
| 34 | 280232426 |
[2,4,9,28,67,137,260,477,847,1456,2459,4097,6766, 11103,18141,29550,48033,77963,126416,204841, 331763,537156,869519,1407325,2277546,3685654, 5964070,9650654,15615716,25267426,40884264, 66152880,107038404,173192616,280232426] |