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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 49 |
| 4 | 338 |
| 5 | 2744 |
| 6 | 26025 |
| 7 | 282419 |
| 8 | 3463502 |
| 9 | 47439030 |
| 10 | 718618117 |
| 11 | 11937743088 |
| 12 | 215896959624 |
| 13 | 4224096594516 |
| 14 | 88919920910684 |
| 15 | 2004237153640098 |
| 16 | 48165411560792500 |
| 17 | 1229462431057436457 |
| 18 | 33221743136066636436 |
| 19 | 947415638925100675208 |
| 20 | 28436953641282225835143 |
[1,2,9,49,338,2744,26025,282419,3463502,47439030, 718618117,11937743088,215896959624,4224096594516, 88919920910684,2004237153640098,48165411560792500, 1229462431057436457,33221743136066636436, 947415638925100675208,28436953641282225835143] |