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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 17 |
| 5 | 113 |
| 6 | 673 |
| 7 | 5669 |
| 8 | 48033 |
| 9 | 494081 |
| 10 | 5387009 |
| 11 | 65835109 |
| 12 | 871869745 |
| 13 | 12394430129 |
| 14 | 192177458593 |
| 15 | 3124415825605 |
| 16 | 55316788832065 |
| 17 | 1014225530028161 |
| 18 | 20139680768683777 |
| 19 | 411568350375102789 |
[1,1,1,5,17,113,673,5669,48033,494081,5387009, 65835109,871869745,12394430129,192177458593, 3124415825605,55316788832065,1014225530028161, 20139680768683777,411568350375102789] |