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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 15 |
| 4 | 47 |
| 5 | 149 |
| 6 | 469 |
| 7 | 1479 |
| 8 | 4663 |
| 9 | 14701 |
| 10 | 46349 |
| 11 | 146127 |
| 12 | 460703 |
| 13 | 1452485 |
| 14 | 4579333 |
| 15 | 14437527 |
| 16 | 45518023 |
| 17 | 143507293 |
| 18 | 452443709 |
| 19 | 1426445343 |
| 20 | 4497236399 |
| 21 | 14178696245 |
| 22 | 44701992373 |
| 23 | 140934546279 |
| 24 | 444332462167 |
| 25 | 1400872547917 |
| 26 | 4416611574893 |
| 27 | 13924505717871 |
[1,1,5,15,47,149,469,1479,4663,14701,46349,146127, 460703,1452485,4579333,14437527,45518023, 143507293,452443709,1426445343,4497236399, 14178696245,44701992373,140934546279,444332462167, 1400872547917,4416611574893,13924505717871] |