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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 2 |
| 5 | 10 |
| 6 | 6 |
| 7 | 63 |
| 8 | 2 |
| 9 | 2 |
| 10 | 20 |
| 11 | 330 |
| 12 | 6 |
| 13 | 390 |
| 14 | 126 |
| 15 | 1323 |
| 16 | 2 |
| 17 | 34 |
| 18 | 4 |
| 19 | 114 |
| 20 | 20 |
| 21 | 100 |
| 22 | 660 |
| 23 | 159390 |
| 24 | 6 |
| 25 | 6 |
| 26 | 780 |
| 27 | 12870 |
| 28 | 126 |
| 29 | 237510 |
| 30 | 2646 |
| 31 | 861273 |
| 32 | 2 |
| 33 | 2 |
| 34 | 68 |
| 35 | 102 |
| 36 | 4 |
| 37 | 740 |
| 38 | 228 |
| 39 | 2394 |
| 40 | 20 |
| 41 | 820 |
| 42 | 200 |
| 43 | 141900 |
| 44 | 660 |
| 45 | 42900 |
| 46 | 318780 |
| 47 | 157317930 |
| 48 | 6 |
| 49 | 102 |
| 50 | 12 |
| 51 | 342 |
| 52 | 780 |
| 53 | 206700 |
[1,1,2,3,2,10,6,63,2,2,20,330,6,390,126,1323,2,34, 4,114,20,100,660,159390,6,6,780,12870,126,237510, 2646,861273,2,2,68,102,4,740,228,2394,20,820,200, 141900,660,42900,318780,157317930,6,102,12,342, 780,206700] |