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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 11 |
| 3 | 39 |
| 4 | 127 |
| 5 | 377 |
| 6 | 1014 |
| 7 | 2518 |
| 8 | 5844 |
| 9 | 12790 |
| 10 | 26582 |
| 11 | 52769 |
| 12 | 100547 |
| 13 | 184661 |
| 14 | 328068 |
| 15 | 565582 |
| 16 | 948764 |
| 17 | 1552366 |
| 18 | 2482688 |
| 19 | 3888261 |
| 20 | 5973327 |
| 21 | 9014649 |
| 22 | 13382250 |
| 23 | 19564750 |
| 24 | 28200044 |
| 25 | 40112142 |
| 26 | 56355074 |
| 27 | 78264849 |
| 28 | 107520547 |
| 29 | 146215717 |
| 30 | 196941352 |
[3,11,39,127,377,1014,2518,5844,12790,26582,52769, 100547,184661,328068,565582,948764,1552366, 2482688,3888261,5973327,9014649,13382250,19564750, 28200044,40112142,56355074,78264849,107520547, 146215717,196941352] |