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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 9 |
| 5 | 46 |
| 6 | 245 |
| 7 | 1474 |
| 8 | 10315 |
| 9 | 82174 |
| 10 | 726591 |
| 11 | 7038632 |
| 12 | 74216949 |
| 13 | 847103658 |
| 14 | 10407684559 |
| 15 | 136932309578 |
| 16 | 1920656913247 |
| 17 | 28609816527534 |
| 18 | 451057722743007 |
| 19 | 7503877147726572 |
| 20 | 131368238149821145 |
| 21 | 2414204385183262842 |
| 22 | 46469039032487849079 |
| 23 | 934915621488296098358 |
| 24 | 19624030747998750863203 |
[1,1,1,2,9,46,245,1474,10315,82174,726591,7038632, 74216949,847103658,10407684559,136932309578, 1920656913247,28609816527534,451057722743007, 7503877147726572,131368238149821145, 2414204385183262842,46469039032487849079, 934915621488296098358,19624030747998750863203] |