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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 12 |
| 4 | 56 |
| 5 | 567 |
| 6 | 5674 |
| 7 | 56749 |
| 8 | 567497 |
| 9 | 5674971 |
| 10 | 122263545 |
| 11 | 2634088227 |
| 12 | 56749710539 |
| 13 | 1222635450364 |
| 14 | 26340882275280 |
| 15 | 567497105399112 |
| 16 | 12226354503645281 |
| 17 | 263408822752809483 |
| 18 | 5674971053991125006 |
[1,2,12,56,567,5674,56749,567497,5674971, 122263545,2634088227,56749710539,1222635450364, 26340882275280,567497105399112,12226354503645281, 263408822752809483,5674971053991125006] |