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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 12 |
| 3 | 116 |
| 4 | 1600 |
| 5 | 28832 |
| 6 | 643864 |
| 7 | 17190392 |
| 8 | 534707296 |
| 9 | 19003345568 |
| 10 | 760054943464 |
| 11 | 33798503960168 |
| 12 | 1654577248619728 |
| 13 | 88437537019736816 |
| 14 | 5125378381513865752 |
| 15 | 320163561707158120568 |
| 16 | 21445740148760729672896 |
| 17 | 1533498858453023915309888 |
[1,2,12,116,1600,28832,643864,17190392,534707296, 19003345568,760054943464,33798503960168, 1654577248619728,88437537019736816, 5125378381513865752,320163561707158120568, 21445740148760729672896,1533498858453023915309888] |