| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 23 |
| 5 | 81 |
| 6 | 361 |
| 7 | 1923 |
| 8 | 13113 |
| 9 | 114433 |
| 10 | 1315783 |
| 11 | 20286135 |
| 12 | 420198791 |
| 13 | 12003852369 |
| 14 | 464295025509 |
| 15 | 25153926114307 |
| 16 | 1847231277588405 |
| 17 | 191568316434991857 |
| 18 | 26902669460380225411 |
| 19 | 5357197471644242149975 |
[1,1,3,7,23,81,361,1923,13113,114433,1315783, 20286135,420198791,12003852369,464295025509, 25153926114307,1847231277588405, 191568316434991857,26902669460380225411, 5357197471644242149975] |