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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 0 |
| 6 | 1 |
| 7 | 3 |
| 8 | 0 |
| 9 | 1 |
| 10 | 6 |
| 11 | 0 |
| 12 | 1 |
| 13 | 25 |
| 14 | 0 |
| 15 | 1 |
| 16 | 60 |
| 17 | 120 |
| 18 | 0 |
| 19 | 1 |
| 20 | 231 |
| 21 | 420 |
| 22 | 0 |
| 23 | 1 |
| 24 | 658 |
| 25 | 2800 |
| 26 | 0 |
| 27 | 1 |
| 28 | 2619 |
| 29 | 20160 |
| 30 | 0 |
| 31 | 1 |
| 32 | 8550 |
| 33 | 105840 |
| 34 | 151200 |
| 35 | 0 |
| 36 | 1 |
| 37 | 35695 |
| 38 | 679140 |
| 39 | 831600 |
| 40 | 0 |
| 41 | 1 |
| 42 | 129756 |
| 43 | 4848360 |
| 44 | 8316000 |
| 45 | 0 |
| 46 | 1 |
| 47 | 568503 |
| 48 | 30356040 |
| 49 | 86486400 |
| 50 | 0 |
| 51 | 1 |
| 52 | 2255344 |
| 53 | 217136920 |
| 54 | 1089728640 |
[1,0,1,0,1,0,1,3,0,1,6,0,1,25,0,1,60,120,0,1,231, 420,0,1,658,2800,0,1,2619,20160,0,1,8550,105840, 151200,0,1,35695,679140,831600,0,1,129756,4848360, 8316000,0,1,568503,30356040,86486400,0,1,2255344, 217136920,1089728640] |