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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 1 |
| 6 | 1 |
| 7 | 0 |
| 8 | 3 |
| 9 | 3 |
| 10 | 5 |
| 11 | 0 |
| 12 | 13 |
| 13 | 9 |
| 14 | 20 |
| 15 | 34 |
| 16 | 0 |
| 17 | 90 |
| 18 | 46 |
| 19 | 70 |
| 20 | 170 |
| 21 | 273 |
| 22 | 0 |
| 23 | 747 |
| 24 | 312 |
| 25 | 360 |
| 26 | 680 |
| 27 | 1638 |
| 28 | 2436 |
| 29 | 0 |
| 30 | 7040 |
| 31 | 2580 |
| 32 | 2435 |
| 33 | 3570 |
| 34 | 7371 |
| 35 | 17052 |
| 36 | 23391 |
| 37 | 0 |
| 38 | 71736 |
| 39 | 24056 |
| 40 | 19800 |
| 41 | 23970 |
| 42 | 39858 |
| 43 | 85260 |
| 44 | 187128 |
| 45 | 237090 |
| 46 | 0 |
| 47 | 774738 |
| 48 | 243483 |
| 49 | 182850 |
| 50 | 193664 |
| 51 | 267813 |
| 52 | 477456 |
| 53 | 1029204 |
| 54 | 2133810 |
| 55 | 2505228 |
[1,0,1,0,1,1,0,3,3,5,0,13,9,20,34,0,90,46,70,170, 273,0,747,312,360,680,1638,2436,0,7040,2580,2435, 3570,7371,17052,23391,0,71736,24056,19800,23970, 39858,85260,187128,237090,0,774738,243483,182850, 193664,267813,477456,1029204,2133810,2505228] |