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| n | a(n) |
|---|---|
| 2 | 2 |
| 3 | 160 |
| 4 | 2448 |
| 5 | 18304 |
| 6 | 90552 |
| 7 | 341568 |
| 8 | 1068928 |
| 9 | 2877696 |
| 10 | 7014204 |
| 11 | 15423200 |
| 12 | 32107456 |
| 13 | 61663104 |
| 14 | 115156144 |
| 15 | 200764608 |
| 16 | 346235904 |
| 17 | 561158400 |
| 18 | 911313450 |
| 19 | 1395016992 |
| 20 | 2158796512 |
| 21 | 3161199104 |
| 22 | 4703221224 |
| 23 | 6631046848 |
| 24 | 9570587136 |
| 25 | 13069048320 |
| 26 | 18346507756 |
| 27 | 24453721152 |
| 28 | 33515655552 |
[2,160,2448,18304,90552,341568,1068928,2877696, 7014204,15423200,32107456,61663104,115156144, 200764608,346235904,561158400,911313450, 1395016992,2158796512,3161199104,4703221224, 6631046848,9570587136,13069048320,18346507756, 24453721152,33515655552] |