The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 24 |
| 3 | 184 |
| 4 | 1664 |
| 5 | 17024 |
| 6 | 192384 |
| 7 | 2366144 |
| 8 | 31362304 |
| 9 | 444907264 |
| 10 | 6720628224 |
| 11 | 107674883584 |
| 12 | 1823884857344 |
| 13 | 32575705493504 |
| 14 | 612054254936064 |
| 15 | 12071987619713024 |
| 16 | 249477777420304384 |
| 17 | 5392386599983366144 |
[1,4,24,184,1664,17024,192384,2366144,31362304, 444907264,6720628224,107674883584,1823884857344, 32575705493504,612054254936064,12071987619713024, 249477777420304384,5392386599983366144] |