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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 4 |
| 2 | 9 |
| 3 | 36 |
| 4 | 36 |
| 5 | 216 |
| 6 | 140 |
| 7 | 1120 |
| 8 | 540 |
| 9 | 5400 |
| 10 | 2079 |
| 11 | 24948 |
| 12 | 8008 |
| 13 | 112112 |
| 14 | 30888 |
| 15 | 494208 |
| 16 | 119340 |
| 17 | 2148120 |
| 18 | 461890 |
| 19 | 9237800 |
| 20 | 1790712 |
| 21 | 39395664 |
| 22 | 6953544 |
| 23 | 166885056 |
| 24 | 27041560 |
| 25 | 703080560 |
| 26 | 105306075 |
| 27 | 2948570100 |
| 28 | 410605200 |
| 29 | 12318156000 |
| 30 | 1602881040 |
| 31 | 51292193280 |
| 32 | 6263890380 |
[2,4,9,36,36,216,140,1120,540,5400,2079,24948, 8008,112112,30888,494208,119340,2148120,461890, 9237800,1790712,39395664,6953544,166885056, 27041560,703080560,105306075,2948570100,410605200, 12318156000,1602881040,51292193280,6263890380] |