The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 0 |
| 3 | 2 |
| 4 | 1 |
| 5 | 12 |
| 6 | 6 |
| 7 | 128 |
| 8 | 78 |
| 9 | 1872 |
| 10 | 1613 |
| 11 | 37600 |
| 12 | 38336 |
| 13 | 990784 |
| 14 | 1124280 |
| 15 | 32333824 |
| 16 | 41622181 |
| 17 | 1272660224 |
| 18 | 1843050734 |
| 19 | 59527313920 |
| 20 | 94591980910 |
| 21 | 3252626013184 |
| 22 | 5602035320753 |
| 23 | 204354574172160 |
| 24 | 380190518533920 |
| 25 | 14594815769038848 |
| 26 | 29179899891380592 |
| 27 | 1174376539738169344 |
[0,1,0,2,1,12,6,128,78,1872,1613,37600,38336, 990784,1124280,32333824,41622181,1272660224, 1843050734,59527313920,94591980910,3252626013184, 5602035320753,204354574172160,380190518533920, 14594815769038848,29179899891380592, 1174376539738169344] |