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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 16 |
| 4 | 149 |
| 5 | 1656 |
| 6 | 22567 |
| 7 | 367144 |
| 8 | 7020729 |
| 9 | 153727408 |
| 10 | 3792553451 |
| 11 | 104109493104 |
| 12 | 3149158146037 |
| 13 | 104087591605336 |
| 14 | 3732676321011471 |
| 15 | 144352230854996056 |
| 16 | 5988802115089340273 |
| 17 | 265333292818927985376 |
| 18 | 12503715930615717645139 |
| 19 | 624511093178389790592352 |
[1,1,3,16,149,1656,22567,367144,7020729,153727408, 3792553451,104109493104,3149158146037, 104087591605336,3732676321011471, 144352230854996056,5988802115089340273, 265333292818927985376,12503715930615717645139, 624511093178389790592352] |