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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 4 |
| 6 | 6 |
| 7 | 18 |
| 8 | 35 |
| 9 | 84 |
| 10 | 137 |
| 11 | 323 |
| 12 | 591 |
| 13 | 1313 |
| 14 | 2033 |
| 15 | 4360 |
| 16 | 7406 |
| 17 | 15581 |
| 18 | 23682 |
| 19 | 49184 |
| 20 | 84017 |
| 21 | 171744 |
| 22 | 259818 |
| 23 | 528784 |
| 24 | 853143 |
| 25 | 1727011 |
| 26 | 2601181 |
| 27 | 5243126 |
| 28 | 8784832 |
| 29 | 17662987 |
| 30 | 26541257 |
| 31 | 53279330 |
| 32 | 86241323 |
| 33 | 172871156 |
| 34 | 259534578 |
| 35 | 519917139 |
[0,0,0,0,1,4,6,18,35,84,137,323,591,1313,2033, 4360,7406,15581,23682,49184,84017,171744,259818, 528784,853143,1727011,2601181,5243126,8784832, 17662987,26541257,53279330,86241323,172871156, 259534578,519917139] |