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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 0 |
| 5 | 6 |
| 6 | 4 |
| 7 | 1 |
| 8 | 0 |
| 9 | 0 |
| 10 | 0 |
| 11 | 48 |
| 12 | 117 |
| 13 | 126 |
| 14 | 84 |
| 15 | 36 |
| 16 | 9 |
| 17 | 1 |
| 18 | 0 |
| 19 | 0 |
| 20 | 0 |
| 21 | 0 |
| 22 | 160 |
| 23 | 1504 |
| 24 | 5496 |
| 25 | 10352 |
| 26 | 12662 |
| 27 | 11424 |
| 28 | 8008 |
| 29 | 4368 |
| 30 | 1820 |
| 31 | 560 |
| 32 | 120 |
| 33 | 16 |
| 34 | 1 |
| 35 | 0 |
| 36 | 0 |
| 37 | 0 |
| 38 | 0 |
| 39 | 0 |
| 40 | 520 |
| 41 | 9000 |
| 42 | 73250 |
| 43 | 356450 |
| 44 | 1135925 |
| 45 | 2500910 |
| 46 | 4024550 |
| 47 | 5038100 |
| 48 | 5160175 |
| 49 | 4451000 |
| 50 | 3268160 |
| 51 | 2042950 |
| 52 | 1081575 |
| 53 | 480700 |
| 54 | 177100 |
| 55 | 53130 |
| 56 | 12650 |
| 57 | 2300 |
| 58 | 300 |
| 59 | 25 |
| 60 | 1 |
[0,1,0,0,6,4,1,0,0,0,48,117,126,84,36,9,1,0,0,0,0, 160,1504,5496,10352,12662,11424,8008,4368,1820, 560,120,16,1,0,0,0,0,0,520,9000,73250,356450, 1135925,2500910,4024550,5038100,5160175,4451000, 3268160,2042950,1081575,480700,177100,53130,12650, 2300,300,25,1] |