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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 0 |
| 5 | 2 |
| 6 | 0 |
| 7 | 2 |
| 8 | 0 |
| 9 | 6 |
| 10 | 0 |
| 11 | 24 |
| 12 | 16 |
| 13 | 0 |
| 14 | 24 |
| 15 | 0 |
| 16 | 544 |
| 17 | 240 |
| 18 | 120 |
| 19 | 0 |
| 20 | 120 |
| 21 | 0 |
| 22 | 22320 |
| 23 | 6608 |
| 24 | 2160 |
| 25 | 960 |
| 26 | 0 |
| 27 | 720 |
| 28 | 0 |
| 29 | 1677488 |
| 30 | 315840 |
| 31 | 70224 |
| 32 | 20160 |
| 33 | 8400 |
| 34 | 0 |
| 35 | 5040 |
| 36 | 0 |
| 37 | 236522496 |
| 38 | 27001984 |
| 39 | 3830400 |
| 40 | 758016 |
| 41 | 201600 |
| 42 | 80640 |
| 43 | 0 |
| 44 | 40320 |
| 45 | 0 |
| 46 | 64026088576 |
| 47 | 4268194560 |
| 48 | 366729600 |
| 49 | 46448640 |
| 50 | 8628480 |
| 51 | 2177280 |
| 52 | 846720 |
| 53 | 0 |
| 54 | 362880 |
[1,0,1,0,0,2,0,2,0,6,0,24,16,0,24,0,544,240,120,0, 120,0,22320,6608,2160,960,0,720,0,1677488,315840, 70224,20160,8400,0,5040,0,236522496,27001984, 3830400,758016,201600,80640,0,40320,0,64026088576, 4268194560,366729600,46448640,8628480,2177280, 846720,0,362880] |