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| n | a(n) |
|---|---|
| 1 | 1680 |
| 2 | 4200 |
| 3 | 27000 |
| 4 | 175392 |
| 5 | 282960 |
| 6 | 707400 |
| 7 | 1668480 |
| 8 | 3344544 |
| 9 | 5658480 |
| 10 | 14146200 |
| 11 | 48644064 |
| 12 | 90008880 |
| 13 | 130110624 |
| 14 | 225022200 |
| 15 | 357994728 |
| 16 | 460763160 |
| 17 | 607281696 |
| 18 | 1926458352 |
| 19 | 3830537880 |
| 20 | 5857651296 |
| 21 | 7840881216 |
| 22 | 8414628480 |
| 23 | 8704032876 |
| 24 | 8843224500 |
| 25 | 14279194512 |
| 26 | 29522053080 |
[1680,4200,27000,175392,282960,707400,1668480, 3344544,5658480,14146200,48644064,90008880, 130110624,225022200,357994728,460763160,607281696, 1926458352,3830537880,5857651296,7840881216, 8414628480,8704032876,8843224500,14279194512, 29522053080] |