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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 1 |
| 6 | 0 |
| 7 | 3 |
| 8 | 0 |
| 9 | 5 |
| 10 | 0 |
| 11 | 12 |
| 12 | 0 |
| 13 | 23 |
| 14 | 0 |
| 15 | 55 |
| 16 | 0 |
| 17 | 114 |
| 18 | 0 |
| 19 | 273 |
| 20 | 0 |
| 21 | 588 |
| 22 | 0 |
| 23 | 1428 |
| 24 | 0 |
| 25 | 3156 |
| 26 | 0 |
| 27 | 7752 |
| 28 | 0 |
| 29 | 17427 |
| 30 | 0 |
| 31 | 43263 |
| 32 | 0 |
| 33 | 98516 |
| 34 | 0 |
| 35 | 246675 |
| 36 | 0 |
| 37 | 567281 |
| 38 | 0 |
| 39 | 1430715 |
| 40 | 0 |
| 41 | 3316521 |
| 42 | 0 |
| 43 | 8414640 |
| 44 | 0 |
| 45 | 19633796 |
| 46 | 0 |
| 47 | 50067108 |
| 48 | 0 |
| 49 | 117464424 |
| 50 | 0 |
| 51 | 300830572 |
| 52 | 0 |
| 53 | 709098696 |
[0,0,1,0,1,0,3,0,5,0,12,0,23,0,55,0,114,0,273,0, 588,0,1428,0,3156,0,7752,0,17427,0,43263,0,98516, 0,246675,0,567281,0,1430715,0,3316521,0,8414640,0, 19633796,0,50067108,0,117464424,0,300830572,0, 709098696] |