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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 4 |
| 6 | 1 |
| 7 | 10 |
| 8 | 5 |
| 9 | 1 |
| 10 | 20 |
| 11 | 40 |
| 12 | 1 |
| 13 | 35 |
| 14 | 175 |
| 15 | 61 |
| 16 | 1 |
| 17 | 56 |
| 18 | 560 |
| 19 | 768 |
| 20 | 1 |
| 21 | 84 |
| 22 | 1470 |
| 23 | 4996 |
| 24 | 1385 |
| 25 | 1 |
| 26 | 120 |
| 27 | 3360 |
| 28 | 22720 |
| 29 | 24320 |
| 30 | 1 |
| 31 | 165 |
| 32 | 6930 |
| 33 | 81730 |
| 34 | 214445 |
| 35 | 50521 |
| 36 | 1 |
| 37 | 220 |
| 38 | 13200 |
| 39 | 248512 |
| 40 | 1288320 |
| 41 | 1152512 |
| 42 | 1 |
| 43 | 286 |
| 44 | 23595 |
| 45 | 665236 |
| 46 | 5986695 |
| 47 | 12989678 |
| 48 | 2702765 |
| 49 | 1 |
| 50 | 364 |
| 51 | 40040 |
| 52 | 1610752 |
| 53 | 23063040 |
| 54 | 98169344 |
| 55 | 76477440 |
[1,1,1,1,1,4,1,10,5,1,20,40,1,35,175,61,1,56,560, 768,1,84,1470,4996,1385,1,120,3360,22720,24320,1, 165,6930,81730,214445,50521,1,220,13200,248512, 1288320,1152512,1,286,23595,665236,5986695, 12989678,2702765,1,364,40040,1610752,23063040, 98169344,76477440] |