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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 64 |
| 3 | 531 |
| 4 | 4525 |
| 5 | 39277 |
| 6 | 345433 |
| 7 | 3067863 |
| 8 | 27452622 |
| 9 | 247134150 |
| 10 | 2235610238 |
| 11 | 20305403848 |
| 12 | 185055810669 |
| 13 | 1691427324498 |
| 14 | 15498568922011 |
| 15 | 142324124371044 |
| 16 | 1309483858158145 |
| 17 | 12068738732981817 |
| 18 | 111399782220575993 |
| 19 | 1029675188344765864 |
| 20 | 9529104863113503460 |
[1,8,64,531,4525,39277,345433,3067863,27452622, 247134150,2235610238,20305403848,185055810669, 1691427324498,15498568922011,142324124371044, 1309483858158145,12068738732981817, 111399782220575993,1029675188344765864, 9529104863113503460] |