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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 1 |
| 6 | 1 |
| 7 | 6 |
| 8 | 6 |
| 9 | 1 |
| 10 | 1 |
| 11 | 15 |
| 12 | 90 |
| 13 | 15 |
| 14 | 1 |
| 15 | 1 |
| 16 | 40 |
| 17 | 600 |
| 18 | 600 |
| 19 | 40 |
| 20 | 1 |
| 21 | 1 |
| 22 | 104 |
| 23 | 4160 |
| 24 | 62400 |
| 25 | 4160 |
| 26 | 104 |
| 27 | 1 |
| 28 | 1 |
| 29 | 273 |
| 30 | 28392 |
| 31 | 1135680 |
| 32 | 1135680 |
| 33 | 28392 |
| 34 | 273 |
| 35 | 1 |
| 36 | 1 |
| 37 | 714 |
| 38 | 194922 |
| 39 | 20271888 |
| 40 | 810875520 |
| 41 | 20271888 |
| 42 | 194922 |
| 43 | 714 |
| 44 | 1 |
| 45 | 1 |
| 46 | 1870 |
| 47 | 1335180 |
| 48 | 364504140 |
[1,1,1,1,2,1,1,6,6,1,1,15,90,15,1,1,40,600,600,40, 1,1,104,4160,62400,4160,104,1,1,273,28392,1135680, 1135680,28392,273,1,1,714,194922,20271888, 810875520,20271888,194922,714,1,1,1870,1335180, 364504140] |