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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 1 |
| 4 | 1 |
| 5 | 20 |
| 6 | 48 |
| 7 | 20 |
| 8 | 1 |
| 9 | 1 |
| 10 | 54 |
| 11 | 405 |
| 12 | 760 |
| 13 | 405 |
| 14 | 54 |
| 15 | 1 |
| 16 | 1 |
| 17 | 112 |
| 18 | 1828 |
| 19 | 8464 |
| 20 | 13840 |
| 21 | 8464 |
| 22 | 1828 |
| 23 | 112 |
| 24 | 1 |
| 25 | 1 |
| 26 | 200 |
| 27 | 5925 |
| 28 | 52800 |
| 29 | 182700 |
| 30 | 273504 |
| 31 | 182700 |
| 32 | 52800 |
| 33 | 5925 |
| 34 | 200 |
| 35 | 1 |
| 36 | 1 |
| 37 | 324 |
| 38 | 15606 |
| 39 | 233300 |
| 40 | 1424925 |
| 41 | 4050864 |
| 42 | 5703096 |
| 43 | 4050864 |
| 44 | 1424925 |
| 45 | 233300 |
| 46 | 15606 |
| 47 | 324 |
| 48 | 1 |
| 49 | 1 |
| 50 | 490 |
| 51 | 35623 |
| 52 | 818300 |
| 53 | 7917371 |
| 54 | 37215794 |
| 55 | 91789005 |
| 56 | 123519792 |
| 57 | 91789005 |
| 58 | 37215794 |
| 59 | 7917371 |
| 60 | 818300 |
| 61 | 35623 |
| 62 | 490 |
| 63 | 1 |
| 64 | 1 |
| 65 | 704 |
| 66 | 73200 |
| 67 | 2430400 |
| 68 | 34657700 |
| 69 | 246781248 |
| 70 | 955910032 |
| 71 | 2116980800 |
| 72 | 2751843600 |
| 73 | 2116980800 |
| 74 | 955910032 |
| 75 | 246781248 |
| 76 | 34657700 |
| 77 | 2430400 |
| 78 | 73200 |
| 79 | 704 |
| 80 | 1 |
[1,1,4,1,1,20,48,20,1,1,54,405,760,405,54,1,1,112, 1828,8464,13840,8464,1828,112,1,1,200,5925,52800, 182700,273504,182700,52800,5925,200,1,1,324,15606, 233300,1424925,4050864,5703096,4050864,1424925, 233300,15606,324,1,1,490,35623,818300,7917371, 37215794,91789005,123519792,91789005,37215794, 7917371,818300,35623,490,1,1,704,73200,2430400, 34657700,246781248,955910032,2116980800, 2751843600,2116980800,955910032,246781248, 34657700,2430400,73200,704,1] |