The OEIS is supported by the many generous donors to the OEIS Foundation.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 4 |
| 3 | 6 |
| 4 | 136 |
| 5 | 660 |
| 6 | 13668 |
| 7 | 128520 |
| 8 | 2846240 |
| 9 | 41368320 |
| 10 | 1021615920 |
| 11 | 20260896480 |
| 12 | 564541372800 |
| 13 | 14159468157120 |
| 14 | 445236762450816 |
| 15 | 13446791658256320 |
| 16 | 474901138629918720 |
| 17 | 16708336544212992000 |
| 18 | 658279512232521209856 |
| 19 | 26360704394322974161920 |
| 20 | 1150065728368040063784960 |
[1,0,4,6,136,660,13668,128520,2846240,41368320, 1021615920,20260896480,564541372800, 14159468157120,445236762450816,13446791658256320, 474901138629918720,16708336544212992000, 658279512232521209856,26360704394322974161920, 1150065728368040063784960] |