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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 0 |
| 6 | 3 |
| 7 | 2 |
| 8 | 9 |
| 9 | 12 |
| 10 | 33 |
| 11 | 56 |
| 12 | 129 |
| 13 | 244 |
| 14 | 523 |
| 15 | 1034 |
| 16 | 2153 |
| 17 | 4336 |
| 18 | 8921 |
| 19 | 18104 |
| 20 | 37065 |
| 21 | 75456 |
| 22 | 154171 |
| 23 | 314266 |
| 24 | 641569 |
| 25 | 1308492 |
| 26 | 2670345 |
| 27 | 5447424 |
| 28 | 11115417 |
| 29 | 22677188 |
| 30 | 46269875 |
| 31 | 94401330 |
| 32 | 192609073 |
| 33 | 392973504 |
| 34 | 801784337 |
| 35 | 1635862800 |
| 36 | 3337639217 |
[0,1,0,1,0,3,2,9,12,33,56,129,244,523,1034,2153, 4336,8921,18104,37065,75456,154171,314266,641569, 1308492,2670345,5447424,11115417,22677188, 46269875,94401330,192609073,392973504,801784337, 1635862800,3337639217] |