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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 13 |
| 5 | 41 |
| 6 | 211 |
| 7 | 967 |
| 8 | 7274 |
| 9 | 44578 |
| 10 | 449551 |
| 11 | 3456641 |
| 12 | 43883797 |
| 13 | 405589549 |
| 14 | 6212792678 |
| 15 | 67022223556 |
| 16 | 1202604514141 |
| 17 | 14825243365517 |
| 18 | 304950638503279 |
| 19 | 4227716923246963 |
| 20 | 98067246206824406 |
| 21 | 1509933505953992386 |
| 22 | 38990856819985996927 |
| 23 | 660048542856323263589 |
| 24 | 18778057160849966289433 |
[1,1,2,4,13,41,211,967,7274,44578,449551,3456641, 43883797,405589549,6212792678,67022223556, 1202604514141,14825243365517,304950638503279, 4227716923246963,98067246206824406, 1509933505953992386,38990856819985996927, 660048542856323263589,18778057160849966289433] |