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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 2 |
| 5 | 6 |
| 6 | 0 |
| 7 | 6 |
| 8 | 28 |
| 9 | 40 |
| 10 | 0 |
| 11 | 16 |
| 12 | 116 |
| 13 | 264 |
| 14 | 224 |
| 15 | 0 |
| 16 | 40 |
| 17 | 444 |
| 18 | 1620 |
| 19 | 2160 |
| 20 | 1152 |
| 21 | 0 |
| 22 | 96 |
| 23 | 1620 |
| 24 | 9156 |
| 25 | 19764 |
| 26 | 16416 |
| 27 | 5632 |
| 28 | 0 |
| 29 | 224 |
| 30 | 5724 |
| 31 | 49848 |
| 32 | 167364 |
| 33 | 224532 |
| 34 | 119232 |
| 35 | 26624 |
| 36 | 0 |
| 37 | 512 |
| 38 | 19764 |
| 39 | 264300 |
| 40 | 1375152 |
| 41 | 2865780 |
| 42 | 2440692 |
| 43 | 839808 |
| 44 | 122880 |
| 45 | 0 |
| 46 | 1152 |
| 47 | 67068 |
| 48 | 1374048 |
[0,1,0,2,6,0,6,28,40,0,16,116,264,224,0,40,444, 1620,2160,1152,0,96,1620,9156,19764,16416,5632,0, 224,5724,49848,167364,224532,119232,26624,0,512, 19764,264300,1375152,2865780,2440692,839808, 122880,0,1152,67068,1374048] |