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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 11 |
| 2 | 61 |
| 3 | 361 |
| 4 | 2311 |
| 5 | 15401 |
| 6 | 104401 |
| 7 | 712531 |
| 8 | 4875781 |
| 9 | 33398201 |
| 10 | 228859951 |
| 11 | 1568486161 |
| 12 | 10750188961 |
| 13 | 73681909211 |
| 14 | 505020747661 |
| 15 | 3461456968201 |
| 16 | 23725161388951 |
| 17 | 162614629188281 |
| 18 | 1114577128871281 |
| 19 | 7639424974303651 |
| 20 | 52361396909490901 |
[1,11,61,361,2311,15401,104401,712531,4875781, 33398201,228859951,1568486161,10750188961, 73681909211,505020747661,3461456968201, 23725161388951,162614629188281,1114577128871281, 7639424974303651,52361396909490901] |