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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 179 |
| 5 | 837 |
| 6 | 4032 |
| 7 | 19449 |
| 8 | 95025 |
| 9 | 464623 |
| 10 | 2287118 |
| 11 | 11267034 |
| 12 | 55704847 |
| 13 | 275630074 |
| 14 | 1366658295 |
| 15 | 6780839615 |
| 16 | 33688009846 |
| 17 | 167454085841 |
| 18 | 833090376329 |
| 19 | 4146412415578 |
| 20 | 20649520773537 |
| 21 | 102871682826652 |
| 22 | 512701830585969 |
| 23 | 2555952678681018 |
| 24 | 12746059166008213 |
| 25 | 63576222439713458 |
| 26 | 317187359821712105 |
[1,2,9,38,179,837,4032,19449,95025,464623,2287118, 11267034,55704847,275630074,1366658295,6780839615, 33688009846,167454085841,833090376329, 4146412415578,20649520773537,102871682826652, 512701830585969,2555952678681018, 12746059166008213,63576222439713458, 317187359821712105] |