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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 30 |
| 6 | 420 |
| 7 | 840 |
| 8 | 1260 |
| 9 | 9240 |
| 10 | 9009 |
| 11 | 240240 |
| 12 | 471240 |
| 13 | 232792560 |
| 14 | 535422888 |
| 15 | 26771144400 |
| 16 | 181704600 |
| 17 | 4822131600 |
| 18 | 36100888223400 |
| 19 | 3702655202400 |
| 20 | 76327592243760 |
| 21 | 737576396429600 |
| 22 | 362291852261631600 |
| 23 | 6416241209619040800 |
[1,2,3,4,30,420,840,1260,9240,9009,240240,471240, 232792560,535422888,26771144400,181704600, 4822131600,36100888223400,3702655202400, 76327592243760,737576396429600,362291852261631600, 6416241209619040800] |