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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 12 |
| 4 | 89 |
| 5 | 407 |
| 6 | 1413 |
| 7 | 3894 |
| 8 | 9431 |
| 9 | 20212 |
| 10 | 39847 |
| 11 | 73177 |
| 12 | 127582 |
| 13 | 211012 |
| 14 | 337186 |
| 15 | 519594 |
| 16 | 777447 |
| 17 | 1134269 |
| 18 | 1620415 |
| 19 | 2264873 |
| 20 | 3114709 |
| 21 | 4209184 |
| 22 | 5609209 |
| 23 | 7378581 |
| 24 | 9594611 |
| 25 | 12326333 |
| 26 | 15688198 |
| 27 | 19779188 |
| 28 | 24721601 |
| 29 | 30646522 |
| 30 | 37727553 |
| 31 | 46093734 |
| 32 | 55983150 |
| 33 | 67558997 |
[0,1,12,89,407,1413,3894,9431,20212,39847,73177, 127582,211012,337186,519594,777447,1134269, 1620415,2264873,3114709,4209184,5609209,7378581, 9594611,12326333,15688198,19779188,24721601, 30646522,37727553,46093734,55983150,67558997] |