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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 2 |
| 5 | 1 |
| 6 | 21 |
| 7 | 56 |
| 8 | 42 |
| 9 | 0 |
| 10 | 0 |
| 11 | 48 |
| 12 | 1 |
| 13 | 315 |
| 14 | 1232 |
| 15 | 3780 |
| 16 | 1344 |
| 17 | 5040 |
| 18 | 5760 |
| 19 | 0 |
| 20 | 0 |
| 21 | 0 |
| 22 | 0 |
| 23 | 0 |
| 24 | 0 |
| 25 | 0 |
| 26 | 2688 |
| 27 | 1 |
| 28 | 6975 |
| 29 | 75392 |
| 30 | 416640 |
| 31 | 666624 |
| 32 | 1249920 |
| 33 | 476160 |
| 34 | 624960 |
| 35 | 0 |
| 36 | 0 |
| 37 | 0 |
| 38 | 833280 |
| 39 | 0 |
| 40 | 1428480 |
| 41 | 1333248 |
| 42 | 0 |
| 43 | 0 |
| 44 | 0 |
| 45 | 0 |
| 46 | 0 |
| 47 | 952320 |
| 48 | 0 |
| 49 | 0 |
| 50 | 0 |
| 51 | 0 |
| 52 | 0 |
| 53 | 0 |
| 54 | 0 |
| 55 | 0 |
| 56 | 0 |
| 57 | 1935360 |
[1,1,3,2,1,21,56,42,0,0,48,1,315,1232,3780,1344, 5040,5760,0,0,0,0,0,0,0,2688,1,6975,75392,416640, 666624,1249920,476160,624960,0,0,0,833280,0, 1428480,1333248,0,0,0,0,0,952320,0,0,0,0,0,0,0,0, 0,1935360] |