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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 22 |
| 3 | 157 |
| 4 | 1100 |
| 5 | 7703 |
| 6 | 53922 |
| 7 | 377457 |
| 8 | 2642200 |
| 9 | 18495403 |
| 10 | 129467822 |
| 11 | 906274757 |
| 12 | 6343923300 |
| 13 | 44407463103 |
| 14 | 310852241722 |
| 15 | 2175965692057 |
| 16 | 15231759844400 |
| 17 | 106622318910803 |
| 18 | 746356232375622 |
| 19 | 5224493626629357 |
[3,22,157,1100,7703,53922,377457,2642200,18495403, 129467822,906274757,6343923300,44407463103, 310852241722,2175965692057,15231759844400, 106622318910803,746356232375622,5224493626629357] |