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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 18 |
| 4 | 0 |
| 5 | 0 |
| 6 | 2430 |
| 7 | 0 |
| 8 | 0 |
| 9 | 640080 |
| 10 | 0 |
| 11 | 0 |
| 12 | 215488350 |
| 13 | 0 |
| 14 | 0 |
| 15 | 84569753268 |
| 16 | 0 |
| 17 | 0 |
| 18 | 36905812607664 |
| 19 | 0 |
| 20 | 0 |
| 21 | 17358832115127360 |
| 22 | 0 |
| 23 | 0 |
| 24 | 8632718277709807710 |
| 25 | 0 |
| 26 | 0 |
| 27 | 4482588877386712735500 |
| 28 | 0 |
| 29 | 0 |
| 30 | 2409165357084756621531180 |
| 31 | 0 |
| 32 | 0 |
| 33 | 1331700439352817463265831040 |
[1,0,0,18,0,0,2430,0,0,640080,0,0,215488350,0,0, 84569753268,0,0,36905812607664,0,0, 17358832115127360,0,0,8632718277709807710,0,0, 4482588877386712735500,0,0, 2409165357084756621531180,0,0, 1331700439352817463265831040] |