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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 2 |
| 6 | 0 |
| 7 | 1 |
| 8 | 2 |
| 9 | 6 |
| 10 | 0 |
| 11 | 1 |
| 12 | 2 |
| 13 | 6 |
| 14 | 15 |
| 15 | 0 |
| 16 | 1 |
| 17 | 2 |
| 18 | 6 |
| 19 | 15 |
| 20 | 40 |
| 21 | 0 |
| 22 | 1 |
| 23 | 2 |
| 24 | 6 |
| 25 | 15 |
| 26 | 40 |
| 27 | 104 |
| 28 | 0 |
| 29 | 1 |
| 30 | 2 |
| 31 | 6 |
| 32 | 15 |
| 33 | 40 |
| 34 | 104 |
| 35 | 273 |
| 36 | 0 |
| 37 | 1 |
| 38 | 2 |
| 39 | 6 |
| 40 | 15 |
| 41 | 40 |
| 42 | 104 |
| 43 | 273 |
| 44 | 714 |
| 45 | 0 |
| 46 | 1 |
| 47 | 2 |
| 48 | 6 |
| 49 | 15 |
| 50 | 40 |
| 51 | 104 |
| 52 | 273 |
| 53 | 714 |
| 54 | 1870 |
| 55 | 0 |
| 56 | 1 |
| 57 | 2 |
| 58 | 6 |
| 59 | 15 |
| 60 | 40 |
| 61 | 104 |
| 62 | 273 |
| 63 | 714 |
| 64 | 1870 |
| 65 | 4895 |
[0,0,1,0,1,2,0,1,2,6,0,1,2,6,15,0,1,2,6,15,40,0,1, 2,6,15,40,104,0,1,2,6,15,40,104,273,0,1,2,6,15,40, 104,273,714,0,1,2,6,15,40,104,273,714,1870,0,1,2, 6,15,40,104,273,714,1870,4895] |