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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 4 |
| 3 | 12 |
| 4 | 20 |
| 5 | 52 |
| 6 | 92 |
| 7 | 192 |
| 8 | 322 |
| 9 | 850 |
| 10 | 1490 |
| 11 | 3122 |
| 12 | 5210 |
| 13 | 13806 |
| 14 | 23834 |
| 15 | 50174 |
| 16 | 82978 |
| 17 | 220462 |
| 18 | 382242 |
| 19 | 800114 |
| 20 | 1334742 |
| 21 | 3530878 |
| 22 | 6101600 |
| 23 | 12843980 |
| 24 | 21242476 |
| 25 | 56440776 |
| 26 | 97845358 |
| 27 | 204811086 |
| 28 | 341687150 |
| 29 | 903923790 |
| 30 | 1562078446 |
| 31 | 3288017550 |
| 32 | 5438140046 |
| 33 | 14448668558 |
[1,3,4,12,20,52,92,192,322,850,1490,3122,5210, 13806,23834,50174,82978,220462,382242,800114, 1334742,3530878,6101600,12843980,21242476, 56440776,97845358,204811086,341687150,903923790, 1562078446,3288017550,5438140046,14448668558] |