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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 2 |
| 8 | 4 |
| 9 | 4 |
| 10 | 2 |
| 11 | 1 |
| 12 | 1 |
| 13 | 2 |
| 14 | 6 |
| 15 | 12 |
| 16 | 16 |
| 17 | 16 |
| 18 | 12 |
| 19 | 6 |
| 20 | 2 |
| 21 | 1 |
| 22 | 1 |
| 23 | 2 |
| 24 | 7 |
| 25 | 18 |
| 26 | 40 |
| 27 | 68 |
| 28 | 96 |
| 29 | 108 |
| 30 | 96 |
| 31 | 68 |
| 32 | 40 |
| 33 | 18 |
| 34 | 7 |
| 35 | 2 |
| 36 | 1 |
| 37 | 1 |
| 38 | 2 |
| 39 | 7 |
| 40 | 20 |
| 41 | 56 |
| 42 | 135 |
| 43 | 281 |
| 44 | 500 |
| 45 | 764 |
| 46 | 982 |
| 47 | 1068 |
| 48 | 982 |
| 49 | 764 |
| 50 | 500 |
| 51 | 281 |
| 52 | 135 |
| 53 | 56 |
| 54 | 20 |
| 55 | 7 |
| 56 | 2 |
| 57 | 1 |
| 58 | 1 |
| 59 | 2 |
| 60 | 7 |
| 61 | 21 |
| 62 | 63 |
| 63 | 181 |
| 64 | 485 |
| 65 | 1159 |
| 66 | 2499 |
| 67 | 4788 |
| 68 | 8074 |
| 69 | 11967 |
| 70 | 15566 |
[0,1,1,1,1,1,2,4,4,2,1,1,2,6,12,16,16,12,6,2,1,1, 2,7,18,40,68,96,108,96,68,40,18,7,2,1,1,2,7,20,56, 135,281,500,764,982,1068,982,764,500,281,135,56, 20,7,2,1,1,2,7,21,63,181,485,1159,2499,4788,8074, 11967,15566] |