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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 72 |
| 4 | 632 |
| 5 | 6352 |
| 6 | 70912 |
| 7 | 864192 |
| 8 | 11371072 |
| 9 | 160333952 |
| 10 | 2409420032 |
| 11 | 38428442112 |
| 12 | 648333665792 |
| 13 | 11538313372672 |
| 14 | 216092576714752 |
| 15 | 4249731095212032 |
| 16 | 87591291183296512 |
| 17 | 1888669450881032192 |
[1,2,10,72,632,6352,70912,864192,11371072, 160333952,2409420032,38428442112,648333665792, 11538313372672,216092576714752,4249731095212032, 87591291183296512,1888669450881032192] |