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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 6487 |
| 4 | 58422 |
| 5 | 569829 |
| 6 | 3352323 |
| 7 | 18437679 |
| 8 | 82994106 |
| 9 | 348339797 |
| 10 | 1310464389 |
| 11 | 4650749220 |
| 12 | 15379052975 |
| 13 | 48512285916 |
| 14 | 145469679888 |
| 15 | 419752300006 |
| 16 | 1165090913961 |
| 17 | 3132596831559 |
| 18 | 8164711662419 |
| 19 | 20718093427629 |
| 20 | 51236693043471 |
| 21 | 123846409657100 |
| 22 | 292897534403136 |
[1,0,0,6487,58422,569829,3352323,18437679, 82994106,348339797,1310464389,4650749220, 15379052975,48512285916,145469679888,419752300006, 1165090913961,3132596831559,8164711662419, 20718093427629,51236693043471,123846409657100, 292897534403136] |