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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 10 |
| 6 | 27 |
| 7 | 88 |
| 8 | 328 |
| 9 | 1460 |
| 10 | 7799 |
| 11 | 51196 |
| 12 | 422521 |
| 13 | 4483460 |
| 14 | 62330116 |
| 15 | 1150504224 |
| 16 | 28434624153 |
| 17 | 945480850638 |
| 18 | 42417674401330 |
| 19 | 2572198227615998 |
| 20 | 211135833162079184 |
| 21 | 23487811567341121158 |
| 22 | 3545543330739039981738 |
| 23 | 727053904070651775719646 |
[1,2,1,2,4,10,27,88,328,1460,7799,51196,422521, 4483460,62330116,1150504224,28434624153, 945480850638,42417674401330,2572198227615998, 211135833162079184,23487811567341121158, 3545543330739039981738,727053904070651775719646] |