The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 15 |
| 2 | 210 |
| 3 | 2940 |
| 4 | 41160 |
| 5 | 576240 |
| 6 | 8067360 |
| 7 | 112943040 |
| 8 | 1581202560 |
| 9 | 22136835840 |
| 10 | 309915701760 |
| 11 | 4338819824640 |
| 12 | 60743477544960 |
| 13 | 850408685629440 |
| 14 | 11905721598812160 |
| 15 | 166680102383370240 |
| 16 | 2333521433367183360 |
| 17 | 32669300067140567040 |
| 18 | 457370200939967938560 |
| 19 | 6403182813159551139840 |
[1,15,210,2940,41160,576240,8067360,112943040, 1581202560,22136835840,309915701760,4338819824640, 60743477544960,850408685629440,11905721598812160, 166680102383370240,2333521433367183360, 32669300067140567040,457370200939967938560, 6403182813159551139840] |