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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 10 |
| 3 | 44 |
| 4 | 242 |
| 5 | 1298 |
| 6 | 7266 |
| 7 | 40632 |
| 8 | 231916 |
| 9 | 1320876 |
| 10 | 7630236 |
| 11 | 43951298 |
| 12 | 255926506 |
| 13 | 1485664226 |
| 14 | 8700154180 |
| 15 | 50792100530 |
| 16 | 298703878402 |
| 17 | 1751415860436 |
| 18 | 10333766393384 |
| 19 | 60797757383394 |
| 20 | 359661008763242 |
| 21 | 2121869963574120 |
[1,10,44,242,1298,7266,40632,231916,1320876, 7630236,43951298,255926506,1485664226,8700154180, 50792100530,298703878402,1751415860436, 10333766393384,60797757383394,359661008763242, 2121869963574120] |