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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 3 |
| 6 | 2 |
| 7 | 10 |
| 8 | 8 |
| 9 | 32 |
| 10 | 18 |
| 11 | 75 |
| 12 | 51 |
| 13 | 292 |
| 14 | 140 |
| 15 | 518 |
| 16 | 534 |
| 17 | 2167 |
| 18 | 1292 |
| 19 | 6055 |
| 20 | 4318 |
| 21 | 23899 |
| 22 | 16589 |
| 23 | 53108 |
| 24 | 46683 |
| 25 | 312340 |
| 26 | 159483 |
| 27 | 567857 |
| 28 | 639256 |
| 29 | 2810965 |
| 30 | 1826974 |
[0,0,0,1,3,2,10,8,32,18,75,51,292,140,518,534, 2167,1292,6055,4318,23899,16589,53108,46683, 312340,159483,567857,639256,2810965,1826974] |