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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 42 |
| 4 | 1560 |
| 5 | 115500 |
| 6 | 14471730 |
| 7 | 2766499428 |
| 8 | 751812526080 |
| 9 | 276002969271480 |
| 10 | 131728355039531250 |
| 11 | 79330842080915572290 |
| 12 | 58863322491995284623360 |
| 13 | 52775356148028535483743372 |
| 14 | 56256397611702084409727330580 |
| 15 | 70329029468732097018514453125000 |
[1,3,42,1560,115500,14471730,2766499428, 751812526080,276002969271480,131728355039531250, 79330842080915572290,58863322491995284623360, 52775356148028535483743372, 56256397611702084409727330580, 70329029468732097018514453125000] |