The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 288 |
| 3 | 5338 |
| 4 | 16338 |
| 5 | 312276 |
| 6 | 1047700 |
| 7 | 20052758 |
| 8 | 71916112 |
| 9 | 1303776080 |
| 10 | 4965633966 |
| 11 | 85069249698 |
| 12 | 342465661280 |
| 13 | 5558842468148 |
| 14 | 23543239967730 |
| 15 | 363597929464136 |
| 16 | 1613453348902866 |
| 17 | 23803367852101370 |
| 18 | 110263048814908764 |
[1,288,5338,16338,312276,1047700,20052758, 71916112,1303776080,4965633966,85069249698, 342465661280,5558842468148,23543239967730, 363597929464136,1613453348902866, 23803367852101370,110263048814908764] |