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| n | a(n) |
|---|---|
| 1 | 28 |
| 2 | 27 |
| 3 | 117 |
| 4 | 260 |
| 5 | 727 |
| 6 | 1857 |
| 7 | 4908 |
| 8 | 12803 |
| 9 | 33565 |
| 10 | 87828 |
| 11 | 229983 |
| 12 | 602057 |
| 13 | 1576252 |
| 14 | 4126635 |
| 15 | 10803717 |
| 16 | 28284452 |
| 17 | 74049703 |
| 18 | 193864593 |
| 19 | 507544140 |
| 20 | 1328767763 |
| 21 | 3478759213 |
| 22 | 9107509812 |
| 23 | 23843770287 |
| 24 | 62423800985 |
| 25 | 163427632732 |
| 26 | 427859097147 |
| 27 | 1120149658773 |
[28,27,117,260,727,1857,4908,12803,33565,87828, 229983,602057,1576252,4126635,10803717,28284452, 74049703,193864593,507544140,1328767763, 3478759213,9107509812,23843770287,62423800985, 163427632732,427859097147,1120149658773] |