The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 15 |
| 3 | 481 |
| 4 | 63499 |
| 5 | 32496361 |
| 6 | 66531801953 |
| 7 | 544920898689805 |
| 8 | 17853080088569676529 |
| 9 | 2339690141788794554403313 |
| 10 | 1226489723856405899902679483839 |
[1,15,481,63499,32496361,66531801953, 544920898689805,17853080088569676529, 2339690141788794554403313, 1226489723856405899902679483839] |