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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 30 |
| 2 | 88 |
| 3 | 260 |
| 4 | 770 |
| 5 | 2284 |
| 6 | 6782 |
| 7 | 20154 |
| 8 | 59928 |
| 9 | 178284 |
| 10 | 530606 |
| 11 | 1579726 |
| 12 | 4704572 |
| 13 | 14014274 |
| 14 | 41756092 |
| 15 | 124439108 |
| 16 | 370913490 |
| 17 | 1105756236 |
| 18 | 3296937150 |
| 19 | 9831523710 |
| 20 | 29321421468 |
| 21 | 87457888182 |
| 22 | 260890934448 |
| 23 | 778326317088 |
[1,30,88,260,770,2284,6782,20154,59928,178284, 530606,1579726,4704572,14014274,41756092, 124439108,370913490,1105756236,3296937150, 9831523710,29321421468,87457888182,260890934448, 778326317088] |