The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 14 |
| 5 | 31 |
| 6 | 230 |
| 7 | 675 |
| 8 | 6902 |
| 9 | 25231 |
| 10 | 329462 |
| 11 | 1441923 |
| 12 | 22934774 |
| 13 | 116914351 |
| 14 | 2193664790 |
| 15 | 12764590275 |
| 16 | 276054834902 |
| 17 | 1805409270031 |
| 18 | 44222780245622 |
| 19 | 321113303226243 |
| 20 | 8787513806478134 |
| 21 | 70146437009397871 |
| 22 | 2121181056663291350 |
| 23 | 18462286083671614275 |
[1,1,2,3,14,31,230,675,6902,25231,329462,1441923, 22934774,116914351,2193664790,12764590275, 276054834902,1805409270031,44222780245622, 321113303226243,8787513806478134, 70146437009397871,2121181056663291350, 18462286083671614275] |