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| n | a(n) |
|---|---|
| 8 | 1 |
| 9 | 16 |
| 10 | 144 |
| 11 | 952 |
| 12 | 5136 |
| 13 | 23904 |
| 14 | 99292 |
| 15 | 376512 |
| 16 | 1324376 |
| 17 | 4372632 |
| 18 | 13673888 |
| 19 | 40787848 |
| 20 | 116713350 |
| 21 | 321861312 |
| 22 | 858693192 |
| 23 | 2223428224 |
| 24 | 5602833292 |
| 25 | 13772292360 |
| 26 | 33089930724 |
| 27 | 77846837848 |
| 28 | 179602530648 |
| 29 | 406914172336 |
| 30 | 906438716196 |
| 31 | 1987418937952 |
| 32 | 4293164981849 |
| 33 | 9144987747024 |
[1,16,144,952,5136,23904,99292,376512,1324376, 4372632,13673888,40787848,116713350,321861312, 858693192,2223428224,5602833292,13772292360, 33089930724,77846837848,179602530648,406914172336, 906438716196,1987418937952,4293164981849, 9144987747024] |