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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 1 |
| 4 | 66 |
| 5 | 18 |
| 6 | 1 |
| 7 | 1056 |
| 8 | 264 |
| 9 | 108 |
| 10 | 36 |
| 11 | 1 |
| 12 | 22176 |
| 13 | 5280 |
| 14 | 3960 |
| 15 | 660 |
| 16 | 540 |
| 17 | 60 |
| 18 | 1 |
| 19 | 576576 |
| 20 | 133056 |
| 21 | 95040 |
| 22 | 43560 |
| 23 | 15840 |
| 24 | 23760 |
| 25 | 3240 |
| 26 | 1320 |
| 27 | 1620 |
| 28 | 90 |
| 29 | 1 |
| 30 | 17873856 |
| 31 | 4036032 |
| 32 | 2794176 |
| 33 | 2439360 |
| 34 | 465696 |
| 35 | 665280 |
| 36 | 304920 |
| 37 | 249480 |
| 38 | 36960 |
| 39 | 83160 |
| 40 | 22680 |
| 41 | 2310 |
[1,6,1,66,18,1,1056,264,108,36,1,22176,5280,3960, 660,540,60,1,576576,133056,95040,43560,15840, 23760,3240,1320,1620,90,1,17873856,4036032, 2794176,2439360,465696,665280,304920,249480,36960, 83160,22680,2310] |