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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 3 |
| 8 | 5 |
| 9 | 7 |
| 10 | 15 |
| 11 | 28 |
| 12 | 47 |
| 13 | 90 |
| 14 | 175 |
| 15 | 319 |
| 16 | 607 |
| 17 | 1181 |
| 18 | 2251 |
| 19 | 4325 |
| 20 | 8449 |
| 21 | 16425 |
| 22 | 31992 |
| 23 | 62823 |
| 24 | 123521 |
| 25 | 243047 |
| 26 | 480316 |
| 27 | 951290 |
| 28 | 1886293 |
| 29 | 3749341 |
| 30 | 7467815 |
| 31 | 14893500 |
| 32 | 29752398 |
| 33 | 59532947 |
| 34 | 119274491 |
| 35 | 239275400 |
| 36 | 480638121 |
| 37 | 966571853 |
| 38 | 1945901716 |
| 39 | 3921699524 |
[1,0,0,1,1,1,3,5,7,15,28,47,90,175,319,607,1181, 2251,4325,8449,16425,31992,62823,123521,243047, 480316,951290,1886293,3749341,7467815,14893500, 29752398,59532947,119274491,239275400,480638121, 966571853,1945901716,3921699524] |