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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 45 |
| 3 | 489 |
| 4 | 4941 |
| 5 | 47241 |
| 6 | 443001 |
| 7 | 4099689 |
| 8 | 37666701 |
| 9 | 344373849 |
| 10 | 3138111873 |
| 11 | 28528236009 |
| 12 | 258893786601 |
| 13 | 2346337687689 |
| 14 | 21242736192681 |
| 15 | 192165056625657 |
| 16 | 1737206429739021 |
| 17 | 15696171011450889 |
| 18 | 141756044468718681 |
| 19 | 1279754258848097769 |
| 20 | 11549782186278421905 |
| 21 | 104208561077631046089 |
[1,9,45,489,4941,47241,443001,4099689,37666701, 344373849,3138111873,28528236009,258893786601, 2346337687689,21242736192681,192165056625657, 1737206429739021,15696171011450889, 141756044468718681,1279754258848097769, 11549782186278421905,104208561077631046089] |