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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 10 |
| 3 | 104 |
| 4 | 1184 |
| 5 | 13952 |
| 6 | 166400 |
| 7 | 1992704 |
| 8 | 23896064 |
| 9 | 286687232 |
| 10 | 3439984640 |
| 11 | 41278767104 |
| 12 | 495341010944 |
| 13 | 5944075354112 |
| 14 | 71328837140480 |
| 15 | 855945777250304 |
| 16 | 10271348253261824 |
| 17 | 123256174744174592 |
| 18 | 1479074079750225920 |
[3,10,104,1184,13952,166400,1992704,23896064, 286687232,3439984640,41278767104,495341010944, 5944075354112,71328837140480,855945777250304, 10271348253261824,123256174744174592, 1479074079750225920] |