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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 5 |
| 4 | 17 |
| 5 | 69 |
| 6 | 299 |
| 7 | 1805 |
| 8 | 9099 |
| 9 | 37331 |
| 10 | 205559 |
| 11 | 4853529 |
| 12 | 49841615 |
| 13 | 789513659 |
| 14 | 9021065871 |
| 15 | 70737031469 |
| 16 | 420565124399 |
| 17 | 22959075244095 |
| 18 | 385032305178719 |
| 19 | 10010973102879761 |
| 20 | 152163983393187399 |
| 21 | 1498273284120348539 |
| 22 | 15639918041915598815 |
| 23 | 1296204202723400597109 |
[0,1,5,17,69,299,1805,9099,37331,205559,4853529, 49841615,789513659,9021065871,70737031469, 420565124399,22959075244095,385032305178719, 10010973102879761,152163983393187399, 1498273284120348539,15639918041915598815, 1296204202723400597109] |