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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 6 |
| 6 | 6 |
| 7 | 3 |
| 8 | 9 |
| 9 | 24 |
| 10 | 54 |
| 11 | 90 |
| 12 | 90 |
| 13 | 4 |
| 14 | 16 |
| 15 | 60 |
| 16 | 204 |
| 17 | 600 |
| 18 | 1440 |
| 19 | 2520 |
| 20 | 2520 |
| 21 | 5 |
| 22 | 25 |
| 23 | 120 |
| 24 | 540 |
| 25 | 2220 |
| 26 | 8100 |
| 27 | 25200 |
| 28 | 63000 |
| 29 | 113400 |
| 30 | 113400 |
| 31 | 6 |
| 32 | 36 |
| 33 | 210 |
| 34 | 1170 |
| 35 | 6120 |
| 36 | 29520 |
| 37 | 128520 |
| 38 | 491400 |
| 39 | 1587600 |
| 40 | 4082400 |
| 41 | 7484400 |
| 42 | 7484400 |
| 43 | 7 |
| 44 | 49 |
| 45 | 336 |
| 46 | 2226 |
| 47 | 14070 |
| 48 | 83790 |
| 49 | 463680 |
| 50 | 2346120 |
| 51 | 10636920 |
| 52 | 42071400 |
| 53 | 139708800 |
| 54 | 366735600 |
| 55 | 681080400 |
| 56 | 681080400 |
[1,1,2,4,6,6,3,9,24,54,90,90,4,16,60,204,600,1440, 2520,2520,5,25,120,540,2220,8100,25200,63000, 113400,113400,6,36,210,1170,6120,29520,128520, 491400,1587600,4082400,7484400,7484400,7,49,336, 2226,14070,83790,463680,2346120,10636920,42071400, 139708800,366735600,681080400,681080400] |