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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 27 |
| 5 | 81 |
| 6 | 311 |
| 7 | 1021 |
| 8 | 4297 |
| 9 | 15419 |
| 10 | 64017 |
| 11 | 234823 |
| 12 | 1027493 |
| 13 | 3966913 |
| 14 | 17125911 |
| 15 | 66455693 |
| 16 | 297225631 |
| 17 | 1194038589 |
| 18 | 5276016417 |
| 19 | 21192497825 |
| 20 | 96118467609 |
| 21 | 396039404493 |
| 22 | 1776784716427 |
| 23 | 7306320511915 |
| 24 | 33459539888437 |
| 25 | 140337672765695 |
| 26 | 636370828530161 |
| 27 | 2661670399860595 |
| 28 | 12275747222956889 |
[1,1,3,7,27,81,311,1021,4297,15419,64017,234823, 1027493,3966913,17125911,66455693,297225631, 1194038589,5276016417,21192497825,96118467609, 396039404493,1776784716427,7306320511915, 33459539888437,140337672765695,636370828530161, 2661670399860595,12275747222956889] |