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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 11 |
| 3 | 105 |
| 4 | 1390 |
| 5 | 23520 |
| 6 | 484247 |
| 7 | 11742927 |
| 8 | 327711230 |
| 9 | 10343198878 |
| 10 | 364237027076 |
| 11 | 14156867852699 |
| 12 | 601927703437645 |
| 13 | 27790427952836499 |
| 14 | 1384496764982434033 |
| 15 | 74027620787319243688 |
| 16 | 4228343290201028904807 |
| 17 | 256946673653717460509502 |
| 18 | 16551666142815138743519611 |
[1,2,11,105,1390,23520,484247,11742927,327711230, 10343198878,364237027076,14156867852699, 601927703437645,27790427952836499, 1384496764982434033,74027620787319243688, 4228343290201028904807,256946673653717460509502, 16551666142815138743519611] |