The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 12 |
| 4 | 87 |
| 5 | 2002 |
| 6 | 59839 |
| 7 | 3862849 |
| 8 | 405580157 |
| 9 | 81304395949 |
| 10 | 28446567810005 |
| 11 | 18268841726936268 |
| 12 | 20937720031330292269 |
| 13 | 43502129718103134992611 |
| 14 | 162426195975365708781849519 |
| 15 | 1095156092719874995442597502324 |
[1,1,12,87,2002,59839,3862849,405580157, 81304395949,28446567810005,18268841726936268, 20937720031330292269,43502129718103134992611, 162426195975365708781849519, 1095156092719874995442597502324] |