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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 21 |
| 4 | 10 |
| 5 | 69905 |
| 6 | 2451 |
| 7 | 1432028818087 |
| 8 | 18166035 |
| 9 | 72719023 |
| 10 | 316138782904777094553940 |
| 11 | 14747027341648947707567131341794256650861 |
| 12 | 1801710500115237891740015 |
| 13 | 37089922913701070144219234699757985931372002942260401897575393 |
[0,1,4,21,10,69905,2451,1432028818087,18166035, 72719023,316138782904777094553940, 14747027341648947707567131341794256650861, 1801710500115237891740015, 37089922913701070144219234699757985931372002942260\ 401897575393] |