The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 27 |
| 4 | 81 |
| 5 | 243 |
| 6 | 540 |
| 7 | 1440 |
| 8 | 3804 |
| 9 | 9960 |
| 10 | 25908 |
| 11 | 67344 |
| 12 | 175884 |
| 13 | 458832 |
| 14 | 1196364 |
| 15 | 3119304 |
| 16 | 8134164 |
| 17 | 21212832 |
| 18 | 55316892 |
| 19 | 144249168 |
| 20 | 376159644 |
| 21 | 980918904 |
| 22 | 2557958964 |
| 23 | 6670420704 |
| 24 | 17394543180 |
| 25 | 45359994336 |
| 26 | 118285895244 |
| 27 | 308455762488 |
| 28 | 804364332180 |
| 29 | 2097551985168 |
| 30 | 5469815336796 |
| 31 | 14263713072192 |
[1,3,9,27,81,243,540,1440,3804,9960,25908,67344, 175884,458832,1196364,3119304,8134164,21212832, 55316892,144249168,376159644,980918904,2557958964, 6670420704,17394543180,45359994336,118285895244, 308455762488,804364332180,2097551985168, 5469815336796,14263713072192] |