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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 5 |
| 3 | 22 |
| 4 | 152 |
| 5 | 2001 |
| 6 | 45097 |
| 7 | 1527506 |
| 8 | 71864928 |
| 9 | 4466430513 |
| 10 | 353828600029 |
| 11 | 34770661312190 |
| 12 | 4148422395161464 |
| 13 | 590479899466175681 |
| 14 | 98824492409739430401 |
| 15 | 19209838771051338898234 |
| 16 | 4291488438323868507946880 |
| 17 | 1091819942877526843993466529 |
| 18 | 313819508664449992611846900981 |
[0,1,5,22,152,2001,45097,1527506,71864928, 4466430513,353828600029,34770661312190, 4148422395161464,590479899466175681, 98824492409739430401,19209838771051338898234, 4291488438323868507946880, 1091819942877526843993466529, 313819508664449992611846900981] |