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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 13 |
| 2 | 121 |
| 3 | 1000 |
| 4 | 7834 |
| 5 | 59719 |
| 6 | 448417 |
| 7 | 3337492 |
| 8 | 24708190 |
| 9 | 182319418 |
| 10 | 1342582762 |
| 11 | 9874401376 |
| 12 | 72571613716 |
| 13 | 533160730795 |
| 14 | 3916383099889 |
| 15 | 28768408020316 |
| 16 | 211347150876598 |
| 17 | 1552952656383862 |
| 18 | 11413589936099950 |
| 19 | 83907782844335248 |
| 20 | 617030596863871276 |
[1,13,121,1000,7834,59719,448417,3337492,24708190, 182319418,1342582762,9874401376,72571613716, 533160730795,3916383099889,28768408020316, 211347150876598,1552952656383862, 11413589936099950,83907782844335248, 617030596863871276] |