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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 1 |
| 7 | 4 |
| 8 | 10 |
| 9 | 20 |
| 10 | 1 |
| 11 | 7 |
| 12 | 28 |
| 13 | 84 |
| 14 | 210 |
| 15 | 1 |
| 16 | 11 |
| 17 | 66 |
| 18 | 286 |
| 19 | 1001 |
| 20 | 3003 |
| 21 | 1 |
| 22 | 16 |
| 23 | 136 |
| 24 | 816 |
| 25 | 3876 |
| 26 | 15504 |
| 27 | 54264 |
| 28 | 1 |
| 29 | 22 |
| 30 | 253 |
| 31 | 2024 |
| 32 | 12650 |
| 33 | 65780 |
| 34 | 296010 |
| 35 | 1184040 |
| 36 | 1 |
| 37 | 29 |
| 38 | 435 |
| 39 | 4495 |
| 40 | 35960 |
| 41 | 237336 |
| 42 | 1344904 |
| 43 | 6724520 |
| 44 | 30260340 |
| 45 | 1 |
| 46 | 37 |
| 47 | 703 |
| 48 | 9139 |
| 49 | 91390 |
| 50 | 749398 |
| 51 | 5245786 |
| 52 | 32224114 |
| 53 | 177232627 |
| 54 | 886163135 |
[1,1,1,1,2,3,1,4,10,20,1,7,28,84,210,1,11,66,286, 1001,3003,1,16,136,816,3876,15504,54264,1,22,253, 2024,12650,65780,296010,1184040,1,29,435,4495, 35960,237336,1344904,6724520,30260340,1,37,703, 9139,91390,749398,5245786,32224114,177232627, 886163135] |