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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 27 |
| 6 | 220 |
| 7 | 5945 |
| 8 | 1307906 |
| 9 | 7775501177 |
| 10 | 10169624642405370 |
| 11 | 79073928376671158546120499 |
| 12 | 804152170591192270227367107671577224679640 |
| 13 | 63587471141272584754077292003976884470033921630214659882200111940371 |
[1,2,3,8,27,220,5945,1307906,7775501177, 10169624642405370,79073928376671158546120499, 804152170591192270227367107671577224679640, 63587471141272584754077292003976884470033921630214\ 659882200111940371] |