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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 24 |
| 3 | 0 |
| 4 | 240 |
| 5 | 0 |
| 6 | 504 |
| 7 | 0 |
| 8 | 480 |
| 9 | 0 |
| 10 | 264 |
| 11 | 0 |
| 12 | 65520 |
| 13 | 0 |
| 14 | 0 |
| 15 | 0 |
| 16 | 16320 |
| 17 | 0 |
| 18 | 28728 |
| 19 | 0 |
| 20 | 13200 |
| 21 | 0 |
| 22 | 552 |
| 23 | 0 |
| 24 | 131040 |
| 25 | 0 |
| 26 | 0 |
| 27 | 0 |
| 28 | 6960 |
| 29 | 0 |
| 30 | 171864 |
| 31 | 0 |
| 32 | 32640 |
| 33 | 0 |
| 34 | 0 |
| 35 | 0 |
| 36 | 138181680 |
| 37 | 0 |
| 38 | 0 |
| 39 | 0 |
| 40 | 1082400 |
| 41 | 0 |
| 42 | 151704 |
| 43 | 0 |
| 44 | 5520 |
| 45 | 0 |
| 46 | 1128 |
| 47 | 0 |
| 48 | 4455360 |
| 49 | 0 |
| 50 | 0 |
| 51 | 0 |
| 52 | 12720 |
| 53 | 0 |
| 54 | 86184 |
| 55 | 0 |
| 56 | 13920 |
| 57 | 0 |
| 58 | 1416 |
| 59 | 0 |
| 60 | 6814407600 |
| 61 | 0 |
| 62 | 0 |
| 63 | 0 |
| 64 | 65280 |
[2,24,0,240,0,504,0,480,0,264,0,65520,0,0,0,16320, 0,28728,0,13200,0,552,0,131040,0,0,0,6960,0, 171864,0,32640,0,0,0,138181680,0,0,0,1082400,0, 151704,0,5520,0,1128,0,4455360,0,0,0,12720,0, 86184,0,13920,0,1416,0,6814407600,0,0,0,65280] |