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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 19 |
| 4 | 110 |
| 5 | 476 |
| 6 | 2477 |
| 7 | 15093 |
| 8 | 86830 |
| 9 | 485290 |
| 10 | 2826902 |
| 11 | 16857116 |
| 12 | 100034453 |
| 13 | 594833357 |
| 14 | 3574477090 |
| 15 | 21611465819 |
| 16 | 130955824174 |
| 17 | 796195223398 |
| 18 | 4860425688176 |
| 19 | 29760574848750 |
| 20 | 182655048136510 |
| 21 | 1123720751229858 |
| 22 | 6929124085148938 |
| 23 | 42811398244528788 |
[1,1,2,19,110,476,2477,15093,86830,485290,2826902, 16857116,100034453,594833357,3574477090, 21611465819,130955824174,796195223398, 4860425688176,29760574848750,182655048136510, 1123720751229858,6929124085148938, 42811398244528788] |