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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 3 |
| 7 | 4 |
| 8 | 7 |
| 9 | 9 |
| 10 | 21 |
| 11 | 20 |
| 12 | 36 |
| 13 | 35 |
| 14 | 66 |
| 15 | 52 |
| 16 | 101 |
| 17 | 84 |
| 18 | 147 |
| 19 | 120 |
| 20 | 224 |
| 21 | 160 |
| 22 | 285 |
| 23 | 220 |
| 24 | 394 |
| 25 | 281 |
| 26 | 483 |
| 27 | 360 |
| 28 | 680 |
| 29 | 455 |
| 30 | 750 |
| 31 | 560 |
| 32 | 1025 |
| 33 | 680 |
| 34 | 1116 |
| 35 | 800 |
| 36 | 1512 |
| 37 | 969 |
| 38 | 1575 |
| 39 | 1148 |
| 40 | 2088 |
| 41 | 1330 |
| 42 | 2160 |
| 43 | 1540 |
| 44 | 2860 |
| 45 | 1771 |
| 46 | 2838 |
| 47 | 2024 |
| 48 | 3734 |
| 49 | 2286 |
| 50 | 3651 |
| 51 | 2640 |
| 52 | 4816 |
| 53 | 2925 |
[0,0,0,0,1,3,4,7,9,21,20,36,35,66,52,101,84,147, 120,224,160,285,220,394,281,483,360,680,455,750, 560,1025,680,1116,800,1512,969,1575,1148,2088, 1330,2160,1540,2860,1771,2838,2024,3734,2286,3651, 2640,4816,2925] |