The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 28 |
| 3 | 244 |
| 4 | 800 |
| 5 | 6576 |
| 6 | 21076 |
| 7 | 173428 |
| 8 | 554040 |
| 9 | 4558536 |
| 10 | 14555468 |
| 11 | 119758148 |
| 12 | 382358832 |
| 13 | 3145930352 |
| 14 | 10044068932 |
| 15 | 82639468964 |
| 16 | 263844008200 |
| 17 | 2170826159272 |
| 18 | 6930820136252 |
| 19 | 57024624645332 |
| 20 | 182063126310336 |
| 21 | 1497958570841456 |
[8,28,244,800,6576,21076,173428,554040,4558536, 14555468,119758148,382358832,3145930352, 10044068932,82639468964,263844008200, 2170826159272,6930820136252,57024624645332, 182063126310336,1497958570841456] |