The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 19 |
| 3 | 143 |
| 4 | 1151 |
| 5 | 9615 |
| 6 | 82223 |
| 7 | 714495 |
| 8 | 6281407 |
| 9 | 55711103 |
| 10 | 497534335 |
| 11 | 4467992831 |
| 12 | 40306810623 |
| 13 | 365002022143 |
| 14 | 3315975217919 |
| 15 | 30208418512895 |
| 16 | 275858397735935 |
| 17 | 2524389197707263 |
| 18 | 23143624647383039 |
| 19 | 212530950189522943 |
| 20 | 1954580341766602751 |
| 21 | 17999540908224323583 |
[1,3,19,143,1151,9615,82223,714495,6281407, 55711103,497534335,4467992831,40306810623, 365002022143,3315975217919,30208418512895, 275858397735935,2524389197707263, 23143624647383039,212530950189522943, 1954580341766602751,17999540908224323583] |