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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 25 |
| 5 | 69 |
| 6 | 191 |
| 7 | 529 |
| 8 | 1465 |
| 9 | 4057 |
| 10 | 11235 |
| 11 | 31113 |
| 12 | 86161 |
| 13 | 238605 |
| 14 | 660767 |
| 15 | 1829857 |
| 16 | 5067409 |
| 17 | 14033137 |
| 18 | 38861859 |
| 19 | 107619849 |
| 20 | 298030825 |
| 21 | 825334485 |
| 22 | 2285592479 |
| 23 | 6329473777 |
| 24 | 17528163337 |
| 25 | 48540608713 |
| 26 | 134423136579 |
[1,1,3,9,25,69,191,529,1465,4057,11235,31113, 86161,238605,660767,1829857,5067409,14033137, 38861859,107619849,298030825,825334485,2285592479, 6329473777,17528163337,48540608713,134423136579] |