The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 3 |
| 4 | 1 |
| 5 | 49 |
| 6 | 732 |
| 7 | 9659 |
| 8 | 190169 |
| 9 | 3225654 |
| 10 | 61896383 |
| 11 | 1360483727 |
| 12 | 30969769918 |
| 13 | 778612992660 |
| 14 | 20749789703573 |
| 15 | 579672756740101 |
| 16 | 17115189938667708 |
| 17 | 525530773660159970 |
| 18 | 16825686497823918869 |
| 19 | 561044904645283065043 |
| 20 | 19368002907483932784642 |
[1,0,3,1,49,732,9659,190169,3225654,61896383, 1360483727,30969769918,778612992660, 20749789703573,579672756740101,17115189938667708, 525530773660159970,16825686497823918869, 561044904645283065043,19368002907483932784642] |