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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 13 |
| 4 | 1742 |
| 5 | 2552030 |
| 6 | 41102995180 |
| 7 | 7281683317103260 |
| 8 | 14189947350338830620680 |
| 9 | 304174136317707285574697584520 |
| 10 | 71722670512982436329410134761448960400 |
| 11 | 186030135925835196854820049614502274473787544400 |
[1,1,13,1742,2552030,41102995180,7281683317103260, 14189947350338830620680, 304174136317707285574697584520, 71722670512982436329410134761448960400, 186030135925835196854820049614502274473787544400] |