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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 4 |
| 6 | 19 |
| 7 | 78 |
| 8 | 217 |
| 9 | 496 |
| 10 | 3961 |
| 11 | 25442 |
| 12 | 105963 |
| 13 | 349504 |
| 14 | 3908059 |
| 15 | 34227438 |
| 16 | 190065457 |
| 17 | 819786496 |
| 18 | 11785687921 |
| 19 | 130746521282 |
| 20 | 907546301523 |
| 21 | 4835447317504 |
| 22 | 84965187064099 |
| 23 | 1141012634368398 |
| 24 | 9504085749177097 |
| 25 | 60283564499562496 |
| 26 | 1251854782837499881 |
[1,1,1,2,3,4,19,78,217,496,3961,25442,105963, 349504,3908059,34227438,190065457,819786496, 11785687921,130746521282,907546301523, 4835447317504,84965187064099,1141012634368398, 9504085749177097,60283564499562496, 1251854782837499881] |