The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 84 |
| 4 | 1614 |
| 5 | 36948 |
| 6 | 947412 |
| 7 | 26334072 |
| 8 | 778107150 |
| 9 | 24133349532 |
| 10 | 778923367284 |
| 11 | 26000354998920 |
| 12 | 893459845502916 |
| 13 | 31496296778304936 |
| 14 | 1135911643635146712 |
| 15 | 41820127450763818896 |
| 16 | 1568983653501973667262 |
| 17 | 59898843849911992994340 |
| 18 | 2324166762372316001442540 |
| 19 | 91565378725229449617874824 |
| 20 | 3659689884915567083966937156 |
| 21 | 148284110214725433666804447912 |
[1,6,84,1614,36948,947412,26334072,778107150, 24133349532,778923367284,26000354998920, 893459845502916,31496296778304936, 1135911643635146712,41820127450763818896, 1568983653501973667262,59898843849911992994340, 2324166762372316001442540, 91565378725229449617874824, 3659689884915567083966937156, 148284110214725433666804447912] |