| n | a(n) |
|---|---|
| 6 | 15 |
| 7 | 210 |
| 8 | 2380 |
| 9 | 26432 |
| 10 | 303660 |
| 11 | 3678840 |
| 12 | 47324376 |
| 13 | 647536032 |
| 14 | 9418945536 |
| 15 | 145410580224 |
| 16 | 2377609752960 |
| 17 | 41082721413120 |
| 18 | 748459539843840 |
| 19 | 14345340443665920 |
| 20 | 288650580508961280 |
| 21 | 6085390148673177600 |
| 22 | 134167064248901376000 |
| 23 | 3088040233895705088000 |
| 24 | 74077507611407752704000 |
| 25 | 1849221425299053367296000 |
[15,210,2380,26432,303660,3678840,47324376, 647536032,9418945536,145410580224,2377609752960, 41082721413120,748459539843840,14345340443665920, 288650580508961280,6085390148673177600, 134167064248901376000,3088040233895705088000, 74077507611407752704000,1849221425299053367296000] |