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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 171 |
| 5 | 796 |
| 6 | 3749 |
| 7 | 17905 |
| 8 | 86307 |
| 9 | 418396 |
| 10 | 2039335 |
| 11 | 9978881 |
| 12 | 48974426 |
| 13 | 240998345 |
| 14 | 1188333118 |
| 15 | 5869632445 |
| 16 | 29035136474 |
| 17 | 143800709201 |
| 18 | 712944995081 |
| 19 | 3537872814069 |
| 20 | 17569705426963 |
| 21 | 87313570041560 |
| 22 | 434165782813249 |
| 23 | 2160005578393606 |
| 24 | 10751118587912161 |
| 25 | 53533873989477849 |
| 26 | 266661692159814558 |
[1,2,9,38,171,796,3749,17905,86307,418396,2039335, 9978881,48974426,240998345,1188333118,5869632445, 29035136474,143800709201,712944995081, 3537872814069,17569705426963,87313570041560, 434165782813249,2160005578393606, 10751118587912161,53533873989477849, 266661692159814558] |