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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 2 |
| 4 | 0 |
| 5 | 2 |
| 6 | 3 |
| 7 | 6 |
| 8 | 6 |
| 9 | 9 |
| 10 | 11 |
| 11 | 19 |
| 12 | 28 |
| 13 | 43 |
| 14 | 66 |
| 15 | 98 |
| 16 | 145 |
| 17 | 219 |
| 18 | 327 |
| 19 | 474 |
| 20 | 744 |
| 21 | 1125 |
| 22 | 1673 |
| 23 | 2481 |
| 24 | 3723 |
| 25 | 5600 |
| 26 | 8415 |
| 27 | 12630 |
| 28 | 18863 |
| 29 | 28395 |
| 30 | 42620 |
| 31 | 63907 |
[1,0,0,2,0,2,3,6,6,9,11,19,28,43,66,98,145,219, 327,474,744,1125,1673,2481,3723,5600,8415,12630, 18863,28395,42620,63907] |