The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 7 |
| 4 | 16 |
| 5 | 21 |
| 6 | 52 |
| 7 | 71 |
| 8 | 160 |
| 9 | 277 |
| 10 | 564 |
| 11 | 1035 |
| 12 | 2176 |
| 13 | 4109 |
| 14 | 8348 |
| 15 | 16467 |
| 16 | 33088 |
| 17 | 65553 |
| 18 | 131740 |
| 19 | 262163 |
| 20 | 525456 |
| 21 | 1048817 |
| 22 | 2099244 |
| 23 | 4194327 |
| 24 | 8393344 |
| 25 | 16777321 |
| 26 | 33562676 |
| 27 | 67109695 |
| 28 | 134234480 |
| 29 | 268435485 |
| 30 | 536905572 |
| 31 | 1073741855 |
| 32 | 2147549824 |
[0,1,4,7,16,21,52,71,160,277,564,1035,2176,4109, 8348,16467,33088,65553,131740,262163,525456, 1048817,2099244,4194327,8393344,16777321,33562676, 67109695,134234480,268435485,536905572,1073741855, 2147549824] |