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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 6 |
| 3 | 1 |
| 4 | 48 |
| 5 | 90 |
| 6 | 1 |
| 7 | 234 |
| 8 | 2214 |
| 9 | 2160 |
| 10 | 1 |
| 11 | 996 |
| 12 | 27432 |
| 13 | 114588 |
| 14 | 71280 |
| 15 | 1 |
| 16 | 4062 |
| 17 | 260748 |
| 18 | 2791800 |
| 19 | 6770628 |
| 20 | 2993760 |
| 21 | 1 |
| 22 | 16344 |
| 23 | 2178630 |
| 24 | 48256344 |
| 25 | 280652364 |
| 26 | 454137840 |
| 27 | 152681760 |
| 28 | 1 |
| 29 | 65490 |
| 30 | 16966530 |
| 31 | 691711920 |
| 32 | 7846782660 |
| 33 | 29157089832 |
| 34 | 34236464400 |
| 35 | 9160905600 |
| 36 | 1 |
| 37 | 262092 |
| 38 | 126820980 |
| 39 | 8851303620 |
| 40 | 174637926180 |
| 41 | 1219804572672 |
| 42 | 3187159638984 |
| 43 | 2871984146400 |
| 44 | 632102486400 |
| 45 | 1 |
| 46 | 1048518 |
| 47 | 924701832 |
| 48 | 105253405560 |
| 49 | 3359003385600 |
| 50 | 39425596747272 |
| 51 | 188635513271256 |
| 52 | 369150976563264 |
| 53 | 265665182896800 |
| 54 | 49303993939200 |
[1,1,6,1,48,90,1,234,2214,2160,1,996,27432,114588, 71280,1,4062,260748,2791800,6770628,2993760,1, 16344,2178630,48256344,280652364,454137840, 152681760,1,65490,16966530,691711920,7846782660, 29157089832,34236464400,9160905600,1,262092, 126820980,8851303620,174637926180,1219804572672, 3187159638984,2871984146400,632102486400,1, 1048518,924701832,105253405560,3359003385600, 39425596747272,188635513271256,369150976563264, 265665182896800,49303993939200] |