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| n | a(n) |
|---|---|
| 1 | 18 |
| 2 | 1197 |
| 3 | 80361 |
| 4 | 5394960 |
| 5 | 362185569 |
| 6 | 24314987763 |
| 7 | 1632363850242 |
| 8 | 109587212856081 |
| 9 | 7357034536009605 |
| 10 | 493907598828348264 |
| 11 | 33158022432323420133 |
| 12 | 2226032671355124283287 |
| 13 | 149442611182684237761426 |
| 14 | 10032689243282040048565125 |
| 15 | 673535162800540841393716209 |
[18,1197,80361,5394960,362185569,24314987763, 1632363850242,109587212856081,7357034536009605, 493907598828348264,33158022432323420133, 2226032671355124283287,149442611182684237761426, 10032689243282040048565125, 673535162800540841393716209] |