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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 6 |
| 4 | 8 |
| 5 | 6 |
| 6 | 20 |
| 7 | 36 |
| 8 | 30 |
| 9 | 20 |
| 10 | 70 |
| 11 | 160 |
| 12 | 168 |
| 13 | 112 |
| 14 | 70 |
| 15 | 252 |
| 16 | 700 |
| 17 | 900 |
| 18 | 720 |
| 19 | 420 |
| 20 | 252 |
| 21 | 924 |
| 22 | 3024 |
| 23 | 4620 |
| 24 | 4400 |
| 25 | 2970 |
| 26 | 1584 |
| 27 | 924 |
| 28 | 3432 |
| 29 | 12936 |
| 30 | 22932 |
| 31 | 25480 |
| 32 | 20020 |
| 33 | 12012 |
| 34 | 6006 |
| 35 | 3432 |
| 36 | 12870 |
| 37 | 54912 |
| 38 | 110880 |
| 39 | 141120 |
| 40 | 127400 |
| 41 | 87360 |
| 42 | 48048 |
| 43 | 22880 |
| 44 | 12870 |
| 45 | 48620 |
[1,2,2,6,8,6,20,36,30,20,70,160,168,112,70,252, 700,900,720,420,252,924,3024,4620,4400,2970,1584, 924,3432,12936,22932,25480,20020,12012,6006,3432, 12870,54912,110880,141120,127400,87360,48048, 22880,12870,48620] |