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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 3 |
| 2 | 8 |
| 3 | 27 |
| 4 | 98 |
| 5 | 363 |
| 6 | 1352 |
| 7 | 5043 |
| 8 | 18818 |
| 9 | 70227 |
| 10 | 262088 |
| 11 | 978123 |
| 12 | 3650402 |
| 13 | 13623483 |
| 14 | 50843528 |
| 15 | 189750627 |
| 16 | 708158978 |
| 17 | 2642885283 |
| 18 | 9863382152 |
| 19 | 36810643323 |
| 20 | 137379191138 |
| 21 | 512706121227 |
| 22 | 1913445293768 |
| 23 | 7141075053843 |
| 24 | 26650854921602 |
[2,3,8,27,98,363,1352,5043,18818,70227,262088, 978123,3650402,13623483,50843528,189750627, 708158978,2642885283,9863382152,36810643323, 137379191138,512706121227,1913445293768, 7141075053843,26650854921602] |