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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 1 |
| 4 | 15 |
| 5 | 20 |
| 6 | 1 |
| 7 | 35 |
| 8 | 168 |
| 9 | 112 |
| 10 | 1 |
| 11 | 66 |
| 12 | 714 |
| 13 | 1680 |
| 14 | 672 |
| 15 | 1 |
| 16 | 110 |
| 17 | 2178 |
| 18 | 11352 |
| 19 | 15840 |
| 20 | 4224 |
| 21 | 1 |
| 22 | 169 |
| 23 | 5434 |
| 24 | 51051 |
| 25 | 156156 |
| 26 | 144144 |
| 27 | 27456 |
| 28 | 1 |
| 29 | 245 |
| 30 | 11830 |
| 31 | 178035 |
| 32 | 972400 |
| 33 | 1953952 |
| 34 | 1281280 |
| 35 | 183040 |
| 36 | 1 |
| 37 | 340 |
| 38 | 23324 |
| 39 | 520676 |
| 40 | 4516798 |
| 41 | 16102944 |
| 42 | 22870848 |
| 43 | 11202048 |
| 44 | 1244672 |
| 45 | 1 |
| 46 | 456 |
| 47 | 42636 |
| 48 | 1337220 |
| 49 | 17073134 |
[1,1,4,1,15,20,1,35,168,112,1,66,714,1680,672,1, 110,2178,11352,15840,4224,1,169,5434,51051,156156, 144144,27456,1,245,11830,178035,972400,1953952, 1281280,183040,1,340,23324,520676,4516798, 16102944,22870848,11202048,1244672,1,456,42636, 1337220,17073134] |