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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 73 |
| 4 | 318 |
| 5 | 1747 |
| 6 | 8216 |
| 7 | 38027 |
| 8 | 173722 |
| 9 | 773529 |
| 10 | 3412416 |
| 11 | 14880845 |
| 12 | 64319686 |
| 13 | 276057515 |
| 14 | 1177345064 |
| 15 | 4994757435 |
| 16 | 21091941082 |
| 17 | 88706514017 |
| 18 | 371741444080 |
| 19 | 1552891025645 |
| 20 | 6468454612966 |
| 21 | 26874623008899 |
| 22 | 111396556833528 |
[1,8,73,318,1747,8216,38027,173722,773529,3412416, 14880845,64319686,276057515,1177345064,4994757435, 21091941082,88706514017,371741444080, 1552891025645,6468454612966,26874623008899, 111396556833528] |