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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | -4 |
| 5 | -20 |
| 6 | 1 |
| 7 | 0 |
| 8 | 28 |
| 9 | 0 |
| 10 | 1 |
| 11 | 20 |
| 12 | -84 |
| 13 | -220 |
| 14 | 924 |
| 15 | 1 |
| 16 | 64 |
| 17 | 924 |
| 18 | 0 |
| 19 | 1820 |
| 20 | 0 |
| 21 | 1 |
| 22 | 140 |
| 23 | 12012 |
| 24 | 48620 |
| 25 | 16796 |
| 26 | -15504 |
| 27 | -48620 |
| 28 | 1 |
| 29 | 256 |
| 30 | 60060 |
| 31 | 2621440 |
| 32 | 2704156 |
| 33 | 0 |
| 34 | 134596 |
| 35 | 0 |
| 36 | 1 |
| 37 | 420 |
| 38 | 204204 |
| 39 | 29745716 |
| 40 | 608435100 |
| 41 | 155117520 |
| 42 | -3801900 |
| 43 | -1184040 |
| 44 | 2704156 |
| 45 | 1 |
| 46 | 640 |
| 47 | 554268 |
| 48 | 187432960 |
| 49 | 15628090140 |
| 50 | 146028888064 |
| 51 | 9075135300 |
| 52 | 0 |
| 53 | 10518300 |
| 54 | 0 |
[1,1,0,1,-4,-20,1,0,28,0,1,20,-84,-220,924,1,64, 924,0,1820,0,1,140,12012,48620,16796,-15504, -48620,1,256,60060,2621440,2704156,0,134596,0,1, 420,204204,29745716,608435100,155117520,-3801900, -1184040,2704156,1,640,554268,187432960, 15628090140,146028888064,9075135300,0,10518300,0] |