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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 0 |
| 6 | 3 |
| 7 | 8 |
| 8 | 0 |
| 9 | 7 |
| 10 | 18 |
| 11 | 0 |
| 12 | 15 |
| 13 | 38 |
| 14 | 0 |
| 15 | 30 |
| 16 | 75 |
| 17 | 0 |
| 18 | 57 |
| 19 | 140 |
| 20 | 0 |
| 21 | 104 |
| 22 | 252 |
| 23 | 0 |
| 24 | 183 |
| 25 | 439 |
| 26 | 0 |
| 27 | 313 |
| 28 | 744 |
| 29 | 0 |
| 30 | 522 |
| 31 | 1232 |
| 32 | 0 |
| 33 | 852 |
| 34 | 1998 |
| 35 | 0 |
| 36 | 1365 |
| 37 | 3182 |
| 38 | 0 |
| 39 | 2150 |
| 40 | 4986 |
| 41 | 0 |
| 42 | 3336 |
| 43 | 7700 |
| 44 | 0 |
| 45 | 5106 |
| 46 | 11736 |
| 47 | 0 |
| 48 | 7719 |
| 49 | 17673 |
| 50 | 0 |
| 51 | 11538 |
| 52 | 26322 |
| 53 | 0 |
| 54 | 17067 |
| 55 | 38808 |
| 56 | 0 |
| 57 | 25004 |
| 58 | 56682 |
| 59 | 0 |
[1,0,1,3,0,3,8,0,7,18,0,15,38,0,30,75,0,57,140,0, 104,252,0,183,439,0,313,744,0,522,1232,0,852,1998, 0,1365,3182,0,2150,4986,0,3336,7700,0,5106,11736, 0,7719,17673,0,11538,26322,0,17067,38808,0,25004, 56682,0] |