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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 5 |
| 3 | 26 |
| 4 | 103 |
| 5 | 2194 |
| 6 | 1223 |
| 7 | 472730 |
| 8 | 556403 |
| 9 | 21323986 |
| 10 | 7281587 |
| 11 | 125858034202 |
| 12 | 180451625 |
| 13 | 121437725363954 |
| 14 | 595953719897 |
| 15 | 26649932810926 |
| 16 | 3211211914492699 |
| 17 | 285050975993898158530 |
| 18 | 549689343118061 |
| 19 | 640611888918574971191834 |
[2,5,26,103,2194,1223,472730,556403,21323986, 7281587,125858034202,180451625,121437725363954, 595953719897,26649932810926,3211211914492699, 285050975993898158530,549689343118061, 640611888918574971191834] |