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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 60 |
| 3 | 1300 |
| 4 | 9800 |
| 5 | 147620 |
| 6 | 402220 |
| 7 | 2011440 |
| 8 | 3920460 |
| 9 | 12336280 |
| 10 | 49568540 |
| 11 | 73958560 |
| 12 | 213810420 |
| 13 | 395841880 |
| 14 | 526780100 |
| 15 | 898267760 |
| 16 | 1847029860 |
| 17 | 3515044180 |
| 18 | 4293364220 |
| 19 | 7538198140 |
| 20 | 10675023240 |
| 21 | 12611185080 |
| 22 | 20257287440 |
| 23 | 27245030540 |
[5,60,1300,9800,147620,402220,2011440,3920460, 12336280,49568540,73958560,213810420,395841880, 526780100,898267760,1847029860,3515044180, 4293364220,7538198140,10675023240,12611185080, 20257287440,27245030540] |