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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 36 |
| 4 | 173 |
| 5 | 769 |
| 6 | 3762 |
| 7 | 17511 |
| 8 | 86361 |
| 9 | 411423 |
| 10 | 2037985 |
| 11 | 9839317 |
| 12 | 48868281 |
| 13 | 237931344 |
| 14 | 1183748118 |
| 15 | 5796419938 |
| 16 | 28871992103 |
| 17 | 141951105936 |
| 18 | 707648354549 |
| 19 | 3489653338760 |
| 20 | 17407086186809 |
| 21 | 86036783957843 |
| 22 | 429365366810146 |
| 23 | 2125989783087252 |
| 24 | 10613449124746823 |
| 25 | 52627074692715082 |
| 26 | 262798854860711897 |
[1,2,9,36,173,769,3762,17511,86361,411423,2037985, 9839317,48868281,237931344,1183748118,5796419938, 28871992103,141951105936,707648354549, 3489653338760,17407086186809,86036783957843, 429365366810146,2125989783087252, 10613449124746823,52627074692715082, 262798854860711897] |