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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 6 |
| 6 | 1 |
| 7 | 6 |
| 8 | 35 |
| 9 | 22 |
| 10 | 1 |
| 11 | 24 |
| 12 | 225 |
| 13 | 310 |
| 14 | 65 |
| 15 | 1 |
| 16 | 120 |
| 17 | 1624 |
| 18 | 3885 |
| 19 | 1975 |
| 20 | 171 |
| 21 | 1 |
| 22 | 720 |
| 23 | 13132 |
| 24 | 47929 |
| 25 | 45080 |
| 26 | 10367 |
| 27 | 420 |
| 28 | 1 |
| 29 | 5040 |
| 30 | 118124 |
| 31 | 606060 |
| 32 | 909489 |
| 33 | 409416 |
| 34 | 48034 |
| 35 | 988 |
| 36 | 1 |
| 37 | 40320 |
| 38 | 1172700 |
| 39 | 7995455 |
| 40 | 17445645 |
| 41 | 13033398 |
| 42 | 3152520 |
| 43 | 204423 |
| 44 | 2259 |
| 45 | 1 |
| 46 | 362880 |
| 47 | 12753576 |
| 48 | 110917400 |
| 49 | 330281930 |
| 50 | 369520305 |
| 51 | 153751773 |
| 52 | 21587950 |
| 53 | 819120 |
| 54 | 5065 |
| 55 | 1 |
[1,1,1,2,6,1,6,35,22,1,24,225,310,65,1,120,1624, 3885,1975,171,1,720,13132,47929,45080,10367,420,1, 5040,118124,606060,909489,409416,48034,988,1, 40320,1172700,7995455,17445645,13033398,3152520, 204423,2259,1,362880,12753576,110917400,330281930, 369520305,153751773,21587950,819120,5065,1] |