The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 23 |
| 5 | 66 |
| 6 | 227 |
| 7 | 713 |
| 8 | 2577 |
| 9 | 8568 |
| 10 | 31421 |
| 11 | 107380 |
| 12 | 402624 |
| 13 | 1417736 |
| 14 | 5348491 |
| 15 | 19083805 |
| 16 | 72852019 |
| 17 | 264474288 |
| 18 | 1012997899 |
| 19 | 3707123478 |
| 20 | 14304055198 |
| 21 | 52928721410 |
| 22 | 204637258329 |
| 23 | 761248539668 |
| 24 | 2957838935076 |
| 25 | 11088044278984 |
| 26 | 43138654656074 |
| 27 | 162322972687620 |
| 28 | 633772214576506 |
| 29 | 2398222243714200 |
[1,1,3,7,23,66,227,713,2577,8568,31421,107380, 402624,1417736,5348491,19083805,72852019, 264474288,1012997899,3707123478,14304055198, 52928721410,204637258329,761248539668, 2957838935076,11088044278984,43138654656074, 162322972687620,633772214576506,2398222243714200] |