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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 2 |
| 7 | 2 |
| 8 | 9 |
| 9 | 11 |
| 10 | 36 |
| 11 | 71 |
| 12 | 151 |
| 13 | 306 |
| 14 | 591 |
| 15 | 1228 |
| 16 | 2469 |
| 17 | 4966 |
| 18 | 10025 |
| 19 | 19591 |
| 20 | 38946 |
| 21 | 75977 |
| 22 | 148585 |
| 23 | 291027 |
| 24 | 579981 |
| 25 | 1152385 |
| 26 | 2280696 |
| 27 | 4470814 |
| 28 | 8817933 |
| 29 | 17244969 |
| 30 | 33819425 |
| 31 | 65976444 |
| 32 | 129933731 |
| 33 | 254791662 |
| 34 | 499516984 |
| 35 | 977417823 |
| 36 | 1914394157 |
| 37 | 3745482924 |
[1,0,0,0,0,1,2,2,9,11,36,71,151,306,591,1228,2469, 4966,10025,19591,38946,75977,148585,291027,579981, 1152385,2280696,4470814,8817933,17244969,33819425, 65976444,129933731,254791662,499516984,977417823, 1914394157,3745482924] |