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| n | a(n) |
|---|---|
| 9 | 1 |
| 10 | 1 |
| 11 | 5 |
| 12 | 19 |
| 13 | 55 |
| 14 | 143 |
| 15 | 335 |
| 16 | 715 |
| 17 | 1430 |
| 18 | 2704 |
| 19 | 4862 |
| 20 | 8398 |
| 21 | 14000 |
| 22 | 22610 |
| 23 | 35530 |
| 24 | 54484 |
| 25 | 81719 |
| 26 | 120175 |
| 27 | 173593 |
| 28 | 246675 |
| 29 | 345345 |
| 30 | 476913 |
| 31 | 650325 |
| 32 | 876525 |
| 33 | 1168710 |
| 34 | 1542684 |
| 35 | 2017356 |
| 36 | 2615104 |
| 37 | 3362260 |
| 38 | 4289780 |
| 39 | 5433736 |
| 40 | 6835972 |
[1,1,5,19,55,143,335,715,1430,2704,4862,8398, 14000,22610,35530,54484,81719,120175,173593, 246675,345345,476913,650325,876525,1168710, 1542684,2017356,2615104,3362260,4289780,5433736, 6835972] |