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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 13 |
| 3 | 157 |
| 4 | 2819 |
| 5 | 67621 |
| 6 | 2036230 |
| 7 | 73907639 |
| 8 | 3142556933 |
| 9 | 153268340377 |
| 10 | 8436526507286 |
| 11 | 517427997295353 |
| 12 | 34994424316034815 |
| 13 | 2587503674068863681 |
| 14 | 207665084850599068022 |
| 15 | 17979537469340405579571 |
| 16 | 1670426465731302891946025 |
| 17 | 165771247503060676475253809 |
| 18 | 17501167047878021578046031334 |
| 19 | 1958599892703021903310163005669 |
[1,2,13,157,2819,67621,2036230,73907639, 3142556933,153268340377,8436526507286, 517427997295353,34994424316034815, 2587503674068863681,207665084850599068022, 17979537469340405579571,1670426465731302891946025, 165771247503060676475253809, 17501167047878021578046031334, 1958599892703021903310163005669] |