The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 42 |
| 4 | 47 |
| 5 | 136 |
| 6 | 183 |
| 7 | 685 |
| 8 | 3608 |
| 9 | 4293 |
| 10 | 20780 |
| 11 | 25073 |
| 12 | 45853 |
| 13 | 70926 |
| 14 | 258631 |
| 15 | 329557 |
| 16 | 588188 |
| 17 | 2094121 |
| 18 | 21529398 |
| 19 | 23623519 |
| 20 | 68776436 |
| 21 | 505058571 |
| 22 | 1078893578 |
| 23 | 18846249397 |
| 24 | 19925142975 |
| 25 | 98546821297 |
| 26 | 2680689317994 |
| 27 | 10821304093273 |
| 28 | 13501993411267 |
[1,2,5,42,47,136,183,685,3608,4293,20780,25073, 45853,70926,258631,329557,588188,2094121,21529398, 23623519,68776436,505058571,1078893578, 18846249397,19925142975,98546821297,2680689317994, 10821304093273,13501993411267] |