The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 12 |
| 6 | 72 |
| 7 | 480 |
| 8 | 864 |
| 9 | 9600 |
| 10 | 108000 |
| 11 | 312000 |
| 12 | 4795200 |
| 13 | 46293120 |
| 14 | 241056000 |
| 15 | 4759413120 |
| 16 | 94182359040 |
| 17 | 478511953920 |
| 18 | 4873965022080 |
| 19 | 122634632171520 |
| 20 | 799554193966080 |
| 21 | 23063946114908160 |
| 22 | 664424069072117760 |
| 23 | 3198456730188840960 |
| 24 | 108184656752428032000 |
| 25 | 2657146152621477888000 |
| 26 | 22850984107452933734400 |
| 27 | 863305241854715928576000 |
| 28 | 15282315334192501724774400 |
| 29 | 151673086024479840160972800 |
[1,1,2,6,12,72,480,864,9600,108000,312000,4795200, 46293120,241056000,4759413120,94182359040, 478511953920,4873965022080,122634632171520, 799554193966080,23063946114908160, 664424069072117760,3198456730188840960, 108184656752428032000,2657146152621477888000, 22850984107452933734400,863305241854715928576000, 15282315334192501724774400, 151673086024479840160972800] |