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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 120 |
| 3 | 1560 |
| 4 | 8400 |
| 5 | 80520 |
| 6 | 185640 |
| 7 | 709920 |
| 8 | 1238040 |
| 9 | 3218160 |
| 10 | 10255560 |
| 11 | 14314560 |
| 12 | 34671960 |
| 13 | 57928080 |
| 14 | 73504200 |
| 15 | 114672480 |
| 16 | 209097720 |
| 17 | 357462120 |
| 18 | 422298120 |
| 19 | 675062520 |
| 20 | 902114640 |
| 21 | 1036535760 |
| 22 | 1538528160 |
| 23 | 1969520280 |
| 24 | 2792029680 |
[15,120,1560,8400,80520,185640,709920,1238040, 3218160,10255560,14314560,34671960,57928080, 73504200,114672480,209097720,357462120,422298120, 675062520,902114640,1036535760,1538528160, 1969520280,2792029680] |