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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 7 |
| 7 | 8 |
| 8 | 12 |
| 9 | 17 |
| 10 | 272 |
| 11 | 315 |
| 12 | 405 |
| 13 | 560 |
| 14 | 728 |
| 15 | 919 |
| 16 | 1578 |
| 17 | 1608 |
| 18 | 4736 |
| 19 | 7751 |
| 20 | 18332 |
| 21 | 22787 |
| 22 | 50005 |
| 23 | 69265 |
| 24 | 91032 |
| 25 | 92591 |
| 26 | 148071 |
| 27 | 168181 |
[0,1,2,3,6,7,8,12,17,272,315,405,560,728,919,1578, 1608,4736,7751,18332,22787,50005,69265,91032, 92591,148071,168181] |