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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 38 |
| 5 | 727 |
| 6 | 26013 |
| 7 | 1597690 |
| 8 | 149248656 |
| 9 | 18919743219 |
| 10 | 3005354096360 |
| 11 | 569226803220234 |
| 12 | 124594074249852576 |
| 13 | 30861014504270954737 |
| 14 | 8520443838646833231236 |
| 15 | 2592150684565935977152860 |
| 16 | 861079753184429687852978432 |
| 17 | 310008316267496041749182487881 |
[1,1,4,38,727,26013,1597690,149248656,18919743219, 3005354096360,569226803220234,124594074249852576, 30861014504270954737,8520443838646833231236, 2592150684565935977152860, 861079753184429687852978432, 310008316267496041749182487881] |