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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 64 |
| 3 | 512 |
| 4 | 4068 |
| 5 | 32152 |
| 6 | 252932 |
| 7 | 1981512 |
| 8 | 15465934 |
| 9 | 120310016 |
| 10 | 933059856 |
| 11 | 7216323640 |
| 12 | 55670133422 |
| 13 | 428465939112 |
| 14 | 3290601897928 |
| 15 | 25221303496496 |
| 16 | 192953793764769 |
| 17 | 1473623863797808 |
| 18 | 11236105478130612 |
| 19 | 85542959337048488 |
[8,64,512,4068,32152,252932,1981512,15465934, 120310016,933059856,7216323640,55670133422, 428465939112,3290601897928,25221303496496, 192953793764769,1473623863797808, 11236105478130612,85542959337048488] |