The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 115 |
| 4 | 1032 |
| 5 | 9049 |
| 6 | 78660 |
| 7 | 681499 |
| 8 | 5896848 |
| 9 | 50998705 |
| 10 | 440975868 |
| 11 | 3812747971 |
| 12 | 32964675480 |
| 13 | 285006414601 |
| 14 | 2464101386292 |
| 15 | 21304030612075 |
| 16 | 184189427142432 |
| 17 | 1592456237959009 |
| 18 | 13767981468377580 |
| 19 | 119034546719719699 |
[1,12,115,1032,9049,78660,681499,5896848,50998705, 440975868,3812747971,32964675480,285006414601, 2464101386292,21304030612075,184189427142432, 1592456237959009,13767981468377580, 119034546719719699] |