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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 2 |
| 5 | 1 |
| 6 | 0 |
| 7 | 6 |
| 8 | 6 |
| 9 | 1 |
| 10 | 0 |
| 11 | 24 |
| 12 | 42 |
| 13 | 8 |
| 14 | 1 |
| 15 | 0 |
| 16 | 120 |
| 17 | 330 |
| 18 | 80 |
| 19 | 10 |
| 20 | 1 |
| 21 | 0 |
| 22 | 720 |
| 23 | 2970 |
| 24 | 860 |
| 25 | 120 |
| 26 | 12 |
| 27 | 1 |
| 28 | 0 |
| 29 | 5040 |
| 30 | 30240 |
| 31 | 10290 |
| 32 | 1540 |
| 33 | 168 |
| 34 | 14 |
| 35 | 1 |
| 36 | 0 |
| 37 | 40320 |
| 38 | 345240 |
| 39 | 136080 |
| 40 | 21490 |
| 41 | 2464 |
| 42 | 224 |
| 43 | 16 |
| 44 | 1 |
| 45 | 0 |
| 46 | 362880 |
| 47 | 4377240 |
| 48 | 1977360 |
| 49 | 326970 |
| 50 | 38808 |
| 51 | 3696 |
| 52 | 288 |
| 53 | 18 |
| 54 | 1 |
[1,0,1,0,2,1,0,6,6,1,0,24,42,8,1,0,120,330,80,10, 1,0,720,2970,860,120,12,1,0,5040,30240,10290,1540, 168,14,1,0,40320,345240,136080,21490,2464,224,16, 1,0,362880,4377240,1977360,326970,38808,3696,288, 18,1] |