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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 3 |
| 7 | 6 |
| 8 | 1 |
| 9 | 3 |
| 10 | 8 |
| 11 | 24 |
| 12 | 6 |
| 13 | 120 |
| 14 | 30 |
| 15 | 20 |
| 16 | 1 |
| 17 | 720 |
| 18 | 15 |
| 19 | 5040 |
| 20 | 20 |
| 21 | 90 |
| 22 | 144 |
| 23 | 40320 |
| 24 | 10 |
| 25 | 40 |
| 26 | 840 |
| 27 | 15 |
| 28 | 90 |
| 29 | 362880 |
| 30 | 120 |
| 31 | 3628800 |
| 32 | 1 |
| 33 | 504 |
| 34 | 5760 |
| 35 | 420 |
| 36 | 45 |
| 37 | 39916800 |
| 38 | 45360 |
| 39 | 3360 |
| 40 | 40 |
| 41 | 479001600 |
| 42 | 630 |
| 43 | 6227020800 |
| 44 | 504 |
| 45 | 210 |
| 46 | 403200 |
| 47 | 87178291200 |
| 48 | 15 |
| 49 | 1260 |
| 50 | 280 |
| 51 | 25920 |
[1,1,1,1,2,3,6,1,3,8,24,6,120,30,20,1,720,15,5040, 20,90,144,40320,10,40,840,15,90,362880,120, 3628800,1,504,5760,420,45,39916800,45360,3360,40, 479001600,630,6227020800,504,210,403200, 87178291200,15,1260,280,25920] |