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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 6 |
| 5 | 1 |
| 6 | 1 |
| 7 | 28 |
| 8 | 70 |
| 9 | 28 |
| 10 | 1 |
| 11 | 1 |
| 12 | 120 |
| 13 | 1820 |
| 14 | 8008 |
| 15 | 12870 |
| 16 | 8008 |
| 17 | 1820 |
| 18 | 120 |
| 19 | 1 |
| 20 | 1 |
| 21 | 496 |
| 22 | 35960 |
| 23 | 906192 |
| 24 | 10518300 |
| 25 | 64512240 |
| 26 | 225792840 |
| 27 | 471435600 |
| 28 | 601080390 |
| 29 | 471435600 |
| 30 | 225792840 |
| 31 | 64512240 |
| 32 | 10518300 |
| 33 | 906192 |
| 34 | 35960 |
| 35 | 496 |
| 36 | 1 |
[1,1,1,1,6,1,1,28,70,28,1,1,120,1820,8008,12870, 8008,1820,120,1,1,496,35960,906192,10518300, 64512240,225792840,471435600,601080390,471435600, 225792840,64512240,10518300,906192,35960,496,1] |