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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 159 |
| 3 | 2485 |
| 4 | 45474 |
| 5 | 959070 |
| 6 | 22963996 |
| 7 | 616224492 |
| 8 | 18331744896 |
| 9 | 599061555136 |
| 10 | 21339235262784 |
| 11 | 823098817664448 |
| 12 | 34183157124707200 |
| 13 | 1520908498941532800 |
| 14 | 72182781516370886400 |
| 15 | 3640264913563748243200 |
| 16 | 194408478299496756556800 |
| 17 | 10961007293837647131724800 |
[1,12,159,2485,45474,959070,22963996,616224492, 18331744896,599061555136,21339235262784, 823098817664448,34183157124707200, 1520908498941532800,72182781516370886400, 3640264913563748243200,194408478299496756556800, 10961007293837647131724800] |