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| n | a(n) |
|---|---|
| 1 | 180 |
| 2 | 1620 |
| 3 | 8820 |
| 4 | 35280 |
| 5 | 87120 |
| 6 | 151380 |
| 7 | 302580 |
| 8 | 380880 |
| 9 | 691920 |
| 10 | 737280 |
| 11 | 808020 |
| 12 | 1393920 |
| 13 | 5020020 |
| 14 | 5767380 |
| 15 | 7712820 |
| 16 | 9604980 |
| 17 | 10281780 |
| 18 | 11160180 |
| 19 | 12450420 |
| 20 | 12736080 |
| 21 | 14723280 |
| 22 | 15138000 |
| 23 | 17186580 |
| 24 | 17860500 |
| 25 | 18663120 |
| 26 | 18779220 |
| 27 | 19129680 |
| 28 | 21300480 |
[180,1620,8820,35280,87120,151380,302580,380880, 691920,737280,808020,1393920,5020020,5767380, 7712820,9604980,10281780,11160180,12450420, 12736080,14723280,15138000,17186580,17860500, 18663120,18779220,19129680,21300480] |