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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 2 |
| 3 | 0 |
| 4 | 6 |
| 5 | 12 |
| 6 | 0 |
| 7 | 20 |
| 8 | 180 |
| 9 | 120 |
| 10 | 0 |
| 11 | 70 |
| 12 | 2380 |
| 13 | 5040 |
| 14 | 1680 |
| 15 | 0 |
| 16 | 252 |
| 17 | 31500 |
| 18 | 163800 |
| 19 | 151200 |
| 20 | 30240 |
| 21 | 0 |
| 22 | 924 |
| 23 | 425964 |
| 24 | 4989600 |
| 25 | 9702000 |
| 26 | 4989600 |
| 27 | 665280 |
| 28 | 0 |
| 29 | 3432 |
| 30 | 5885880 |
| 31 | 150174024 |
| 32 | 554954400 |
| 33 | 554954400 |
| 34 | 181621440 |
| 35 | 17297280 |
[1,0,2,0,6,12,0,20,180,120,0,70,2380,5040,1680,0, 252,31500,163800,151200,30240,0,924,425964, 4989600,9702000,4989600,665280,0,3432,5885880, 150174024,554954400,554954400,181621440,17297280] |