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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 0 |
| 5 | 6 |
| 6 | 6 |
| 7 | 0 |
| 8 | 0 |
| 9 | 6 |
| 10 | 174 |
| 11 | 840 |
| 12 | 2520 |
| 13 | 5040 |
| 14 | 5040 |
| 15 | 0 |
| 16 | 0 |
| 17 | 0 |
| 18 | 840 |
| 19 | 24360 |
| 20 | 335160 |
| 21 | 3553200 |
| 22 | 32382000 |
| 23 | 259459200 |
| 24 | 1816214400 |
| 25 | 10897286400 |
| 26 | 54486432000 |
| 27 | 217945728000 |
| 28 | 653837184000 |
| 29 | 1307674368000 |
| 30 | 1307674368000 |
| 31 | 0 |
| 32 | 0 |
| 33 | 0 |
| 34 | 2520 |
| 35 | 335160 |
| 36 | 15198120 |
| 37 | 476496720 |
| 38 | 12767000400 |
| 39 | 314181504000 |
| 40 | 7288444800000 |
[1,0,1,0,0,6,6,0,0,6,174,840,2520,5040,5040,0,0,0, 840,24360,335160,3553200,32382000,259459200, 1816214400,10897286400,54486432000,217945728000, 653837184000,1307674368000,1307674368000,0,0,0, 2520,335160,15198120,476496720,12767000400, 314181504000,7288444800000] |