The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 3 |
| 3 | 24 |
| 4 | 105 |
| 5 | 492 |
| 6 | 2283 |
| 7 | 10608 |
| 8 | 49281 |
| 9 | 228948 |
| 10 | 1063635 |
| 11 | 4941384 |
| 12 | 22956441 |
| 13 | 106649916 |
| 14 | 495468987 |
| 15 | 2301825696 |
| 16 | 10693709745 |
| 17 | 49680316068 |
| 18 | 230802393507 |
| 19 | 1072250522232 |
| 20 | 4981409269449 |
| 21 | 23142388644492 |
| 22 | 107513782386315 |
| 23 | 499482295478736 |
| 24 | 2320470529073889 |
[4,3,24,105,492,2283,10608,49281,228948,1063635, 4941384,22956441,106649916,495468987,2301825696, 10693709745,49680316068,230802393507, 1072250522232,4981409269449,23142388644492, 107513782386315,499482295478736,2320470529073889] |