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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 60 |
| 3 | 60 |
| 4 | 264 |
| 5 | 612 |
| 6 | 264 |
| 7 | 1176 |
| 8 | 6696 |
| 9 | 6696 |
| 10 | 1176 |
| 11 | 5280 |
| 12 | 74736 |
| 13 | 190740 |
| 14 | 74736 |
| 15 | 5280 |
| 16 | 23712 |
| 17 | 840456 |
| 18 | 5514360 |
| 19 | 5514360 |
| 20 | 840456 |
| 21 | 23712 |
| 22 | 106560 |
| 23 | 9474840 |
| 24 | 161370036 |
| 25 | 419434596 |
| 26 | 161370036 |
| 27 | 9474840 |
| 28 | 106560 |
| 29 | 478848 |
| 30 | 106904016 |
| 31 | 4730218284 |
[15,60,60,264,612,264,1176,6696,6696,1176,5280, 74736,190740,74736,5280,23712,840456,5514360, 5514360,840456,23712,106560,9474840,161370036, 419434596,161370036,9474840,106560,478848, 106904016,4730218284] |