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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 16 |
| 4 | 122 |
| 5 | 1096 |
| 6 | 10322 |
| 7 | 102856 |
| 8 | 1054322 |
| 9 | 11104336 |
| 10 | 119175842 |
| 11 | 1299844576 |
| 12 | 14360860202 |
| 13 | 160403229016 |
| 14 | 1808192266322 |
| 15 | 20545886851096 |
| 16 | 235069897341122 |
| 17 | 2705792876561056 |
| 18 | 31312112470672322 |
| 19 | 364079737402597936 |
| 20 | 4251402314343575642 |
| 21 | 49835252820257276776 |
[1,2,16,122,1096,10322,102856,1054322,11104336, 119175842,1299844576,14360860202,160403229016, 1808192266322,20545886851096,235069897341122, 2705792876561056,31312112470672322, 364079737402597936,4251402314343575642, 49835252820257276776] |