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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 1632 |
| 3 | 83518 |
| 4 | 4217066 |
| 5 | 217145076 |
| 6 | 11168045764 |
| 7 | 573985849362 |
| 8 | 29502860015392 |
| 9 | 1516477156642474 |
| 10 | 77948189988273490 |
| 11 | 4006599407114049916 |
| 12 | 205942439718841896456 |
| 13 | 10585607796890601624858 |
| 14 | 544108792600210068202950 |
[21,1632,83518,4217066,217145076,11168045764, 573985849362,29502860015392,1516477156642474, 77948189988273490,4006599407114049916, 205942439718841896456,10585607796890601624858, 544108792600210068202950] |