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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 140 |
| 2 | 60060 |
| 3 | 29745716 |
| 4 | 15628090140 |
| 5 | 8480843582640 |
| 6 | 4697400936504900 |
| 7 | 2638798257262351800 |
| 8 | 1497753729733989900060 |
| 9 | 856840435680656569701776 |
| 10 | 493243073668546377605912560 |
| 11 | 285369375758780754651194529300 |
| 12 | 165789876049841088844342275759300 |
[1,140,60060,29745716,15628090140,8480843582640, 4697400936504900,2638798257262351800, 1497753729733989900060,856840435680656569701776, 493243073668546377605912560, 285369375758780754651194529300, 165789876049841088844342275759300] |