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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 22 |
| 3 | 82 |
| 4 | 306 |
| 5 | 1142 |
| 6 | 4250 |
| 7 | 15806 |
| 8 | 58730 |
| 9 | 218142 |
| 10 | 810074 |
| 11 | 3007886 |
| 12 | 11167914 |
| 13 | 41463774 |
| 14 | 153942330 |
| 15 | 571535534 |
| 16 | 2121906442 |
| 17 | 7877856190 |
| 18 | 29247532442 |
| 19 | 108585059214 |
| 20 | 403135208426 |
| 21 | 1496688037406 |
| 22 | 5556634000122 |
| 23 | 20629669372526 |
| 24 | 76590116106186 |
| 25 | 284349965403518 |
| 26 | 1055683240842074 |
| 27 | 3919350217589838 |
| 28 | 14551056119534250 |
| 29 | 54022534883643358 |
[1,6,22,82,306,1142,4250,15806,58730,218142, 810074,3007886,11167914,41463774,153942330, 571535534,2121906442,7877856190,29247532442, 108585059214,403135208426,1496688037406, 5556634000122,20629669372526,76590116106186, 284349965403518,1055683240842074,3919350217589838, 14551056119534250,54022534883643358] |