The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 5 |
| 5 | 9 |
| 6 | 12 |
| 7 | 17 |
| 8 | 21 |
| 9 | 27 |
| 10 | 33 |
| 11 | 41 |
| 12 | 48 |
| 13 | 56 |
| 14 | 65 |
| 15 | 75 |
| 16 | 85 |
| 17 | 96 |
| 18 | 108 |
| 19 | 121 |
| 20 | 133 |
[0,1,1,4,5,9,12,17,21,27,33,41,48,56,65,75,85,96, 108,121,133] |