The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 17 |
| 6 | 46 |
| 7 | 127 |
| 8 | 385 |
| 9 | 1138 |
| 10 | 3557 |
| 11 | 11332 |
| 12 | 36949 |
| 13 | 122262 |
| 14 | 415624 |
| 15 | 1427497 |
| 16 | 4962532 |
| 17 | 17550068 |
| 18 | 62626410 |
| 19 | 225373569 |
| 20 | 821372128 |
| 21 | 3016299522 |
| 22 | 11145989333 |
| 23 | 41593856129 |
| 24 | 156190755015 |
| 25 | 589476598936 |
| 26 | 2241899251552 |
| 27 | 8571688434648 |
| 28 | 32908712661363 |
| 29 | 127130928921437 |
| 30 | 493347655801103 |
| 31 | 1921175991853967 |
[1,1,2,3,8,17,46,127,385,1138,3557,11332,36949, 122262,415624,1427497,4962532,17550068,62626410, 225373569,821372128,3016299522,11145989333, 41593856129,156190755015,589476598936, 2241899251552,8571688434648,32908712661363, 127130928921437,493347655801103,1921175991853967] |