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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 113 |
| 5 | 4505 |
| 6 | 324545 |
| 7 | 34312317 |
| 8 | 5171466801 |
| 9 | 1036525185393 |
| 10 | 268061777199361 |
| 11 | 86654517306871861 |
| 12 | 34236056076864607345 |
| 13 | 16224034929841344607625 |
| 14 | 9077085568599515191480769 |
| 15 | 5918716657866577845713460525 |
| 16 | 4447229534037550877037585953073 |
| 17 | 3813957492790787345317821024498657 |
| 18 | 3702048025219670721125627874960351233 |
[1,1,5,113,4505,324545,34312317,5171466801, 1036525185393,268061777199361,86654517306871861, 34236056076864607345,16224034929841344607625, 9077085568599515191480769, 5918716657866577845713460525, 4447229534037550877037585953073, 3813957492790787345317821024498657, 3702048025219670721125627874960351233] |