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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 4 |
| 7 | 6 |
| 8 | 8 |
| 9 | 8 |
| 10 | 6 |
| 11 | 3 |
| 12 | 1 |
| 13 | 1 |
| 14 | 3 |
| 15 | 9 |
| 16 | 24 |
| 17 | 60 |
| 18 | 138 |
| 19 | 294 |
| 20 | 579 |
| 21 | 1053 |
| 22 | 1767 |
| 23 | 2739 |
| 24 | 3924 |
| 25 | 5196 |
| 26 | 6352 |
| 27 | 7152 |
| 28 | 7389 |
| 29 | 6969 |
| 30 | 5961 |
| 31 | 4587 |
| 32 | 3144 |
| 33 | 1896 |
| 34 | 990 |
| 35 | 438 |
| 36 | 159 |
| 37 | 45 |
| 38 | 9 |
| 39 | 1 |
| 40 | 1 |
| 41 | 4 |
| 42 | 16 |
| 43 | 60 |
| 44 | 216 |
| 45 | 744 |
| 46 | 2460 |
| 47 | 7818 |
| 48 | 23910 |
| 49 | 70446 |
| 50 | 200160 |
| 51 | 549006 |
| 52 | 1455132 |
| 53 | 3730846 |
| 54 | 9262712 |
[1,1,1,1,1,2,4,6,8,8,6,3,1,1,3,9,24,60,138,294, 579,1053,1767,2739,3924,5196,6352,7152,7389,6969, 5961,4587,3144,1896,990,438,159,45,9,1,1,4,16,60, 216,744,2460,7818,23910,70446,200160,549006, 1455132,3730846,9262712] |