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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 6 |
| 4 | 3 |
| 5 | 1 |
| 6 | 20 |
| 7 | 110 |
| 8 | 180 |
| 9 | 58 |
| 10 | 1 |
| 11 | 42 |
| 12 | 657 |
| 13 | 4890 |
| 14 | 18343 |
| 15 | 33792 |
| 16 | 27380 |
| 17 | 7416 |
| 18 | 280 |
| 19 | 1 |
| 20 | 72 |
| 21 | 2172 |
| 22 | 36028 |
| 23 | 362643 |
| 24 | 2307376 |
| 25 | 9382388 |
| 26 | 24121696 |
| 27 | 37965171 |
| 28 | 34431880 |
| 29 | 16172160 |
| 30 | 3219364 |
| 31 | 170985 |
| 32 | 1 |
| 33 | 110 |
| 34 | 5375 |
| 35 | 154434 |
| 36 | 2911226 |
| 37 | 38049764 |
| 38 | 355340561 |
| 39 | 2408715568 |
[1,1,1,6,3,1,20,110,180,58,1,42,657,4890,18343, 33792,27380,7416,280,1,72,2172,36028,362643, 2307376,9382388,24121696,37965171,34431880, 16172160,3219364,170985,1,110,5375,154434,2911226, 38049764,355340561,2408715568] |