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| n | a(n) |
|---|---|
| 6 | 4 |
| 7 | 832 |
| 8 | 22708 |
| 9 | 312956 |
| 10 | 2716096 |
| 11 | 17117832 |
| 12 | 84871680 |
| 13 | 349093856 |
| 14 | 1239869972 |
| 15 | 3905117168 |
| 16 | 11139611892 |
| 17 | 29224290600 |
| 18 | 71402912960 |
| 19 | 164029487484 |
| 20 | 357164398040 |
| 21 | 741835920276 |
| 22 | 1477798367368 |
| 23 | 2836053660668 |
| 24 | 5263672510684 |
| 25 | 9478352925488 |
| 26 | 16606678238496 |
| 27 | 28378012168908 |
[4,832,22708,312956,2716096,17117832,84871680, 349093856,1239869972,3905117168,11139611892, 29224290600,71402912960,164029487484,357164398040, 741835920276,1477798367368,2836053660668, 5263672510684,9478352925488,16606678238496, 28378012168908] |