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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 5 |
| 6 | 0 |
| 7 | 4 |
| 8 | 21 |
| 9 | 35 |
| 10 | 0 |
| 11 | 18 |
| 12 | 101 |
| 13 | 210 |
| 14 | 175 |
| 15 | 0 |
| 16 | 48 |
| 17 | 286 |
| 18 | 671 |
| 19 | 770 |
| 20 | 385 |
| 21 | 0 |
| 22 | 33168 |
| 23 | 207974 |
| 24 | 531531 |
| 25 | 715715 |
| 26 | 525525 |
| 27 | 175175 |
| 28 | 0 |
| 29 | 8640 |
| 30 | 56568 |
| 31 | 154466 |
| 32 | 231231 |
| 33 | 205205 |
| 34 | 105105 |
| 35 | 25025 |
| 36 | 0 |
| 37 | 1562544 |
| 38 | 10615548 |
| 39 | 30582796 |
| 40 | 49534277 |
| 41 | 49689640 |
| 42 | 31481450 |
| 43 | 11911900 |
[1,0,1,0,1,5,0,4,21,35,0,18,101,210,175,0,48,286, 671,770,385,0,33168,207974,531531,715715,525525, 175175,0,8640,56568,154466,231231,205205,105105, 25025,0,1562544,10615548,30582796,49534277, 49689640,31481450,11911900] |