The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 9 |
| 4 | 19 |
| 5 | 41 |
| 6 | 88 |
| 7 | 195 |
| 8 | 418 |
| 9 | 1033 |
| 10 | 2195 |
| 11 | 4705 |
| 12 | 10282 |
| 13 | 21850 |
| 14 | 49160 |
| 15 | 104465 |
| 16 | 223780 |
| 17 | 550294 |
| 18 | 1186344 |
| 19 | 2525345 |
| 20 | 5514438 |
| 21 | 11817057 |
| 22 | 26297040 |
| 23 | 56201282 |
| 24 | 138856076 |
| 25 | 295217708 |
| 26 | 632609378 |
| 27 | 1382640428 |
| 28 | 2974062096 |
| 29 | 6603081730 |
| 30 | 14149570820 |
| 31 | 34976354857 |
| 32 | 74361996963 |
[1,2,4,9,19,41,88,195,418,1033,2195,4705,10282, 21850,49160,104465,223780,550294,1186344,2525345, 5514438,11817057,26297040,56201282,138856076, 295217708,632609378,1382640428,2974062096, 6603081730,14149570820,34976354857,74361996963] |