The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 97 |
| 5 | 981 |
| 6 | 12331 |
| 7 | 187153 |
| 8 | 3319233 |
| 9 | 67362697 |
| 10 | 1540796851 |
| 11 | 39256807701 |
| 12 | 1102344130273 |
| 13 | 33822265578973 |
| 14 | 1125785761963227 |
| 15 | 40407886961046361 |
| 16 | 1555858721974047361 |
| 17 | 63972335301256871313 |
| 18 | 2797676940942967706083 |
[1,1,3,13,97,981,12331,187153,3319233,67362697, 1540796851,39256807701,1102344130273, 33822265578973,1125785761963227,40407886961046361, 1555858721974047361,63972335301256871313, 2797676940942967706083] |