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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 2 |
| 5 | 1 |
| 6 | 0 |
| 7 | 6 |
| 8 | 8 |
| 9 | 3 |
| 10 | 0 |
| 11 | 24 |
| 12 | 64 |
| 13 | 59 |
| 14 | 18 |
| 15 | 0 |
| 16 | 120 |
| 17 | 574 |
| 18 | 970 |
| 19 | 695 |
| 20 | 180 |
| 21 | 0 |
| 22 | 720 |
| 23 | 5858 |
| 24 | 16124 |
| 25 | 20240 |
| 26 | 11955 |
| 27 | 2700 |
| 28 | 0 |
| 29 | 5040 |
| 30 | 67752 |
| 31 | 285264 |
| 32 | 556591 |
| 33 | 559895 |
| 34 | 282555 |
| 35 | 56700 |
| 36 | 0 |
| 37 | 40320 |
| 38 | 880584 |
| 39 | 5459712 |
| 40 | 15519287 |
| 41 | 23585870 |
| 42 | 19879370 |
| 43 | 8780940 |
| 44 | 1587600 |
| 45 | 0 |
| 46 | 362880 |
| 47 | 12746208 |
| 48 | 113511982 |
| 49 | 451541898 |
| 50 | 971214825 |
| 51 | 1213062690 |
| 52 | 882179550 |
| 53 | 347072040 |
| 54 | 57153600 |
[1,0,1,0,2,1,0,6,8,3,0,24,64,59,18,0,120,574,970, 695,180,0,720,5858,16124,20240,11955,2700,0,5040, 67752,285264,556591,559895,282555,56700,0,40320, 880584,5459712,15519287,23585870,19879370,8780940, 1587600,0,362880,12746208,113511982,451541898, 971214825,1213062690,882179550,347072040,57153600] |