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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 47 |
| 5 | 655 |
| 6 | 12145 |
| 7 | 281645 |
| 8 | 7848575 |
| 9 | 255581095 |
| 10 | 9527142625 |
| 11 | 400145871125 |
| 12 | 18700514207375 |
| 13 | 962618343061375 |
| 14 | 54121350164907025 |
| 15 | 3300097924150152125 |
| 16 | 216926019220561025375 |
| 17 | 15292057853288541700375 |
| 18 | 1150861860384703732890625 |
| 19 | 92099021113080260667513125 |
[1,1,5,47,655,12145,281645,7848575,255581095, 9527142625,400145871125,18700514207375, 962618343061375,54121350164907025, 3300097924150152125,216926019220561025375, 15292057853288541700375,1150861860384703732890625, 92099021113080260667513125] |