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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 505 |
| 4 | 5905 |
| 5 | 596405 |
| 6 | 1971005 |
| 7 | 199071505 |
| 8 | 515151005 |
| 9 | 581457505 |
| 10 | 618181105 |
| 11 | 2327756905 |
| 12 | 11855474405 |
| 13 | 19555113485 |
| 14 | 31361954905 |
| 15 | 101901244565 |
| 16 | 235103447405 |
| 17 | 305354088005 |
| 18 | 395331063745 |
| 19 | 600905819065 |
| 20 | 608393336905 |
| 21 | 686701313405 |
| 22 | 730071885005 |
[1,5,505,5905,596405,1971005,199071505,515151005, 581457505,618181105,2327756905,11855474405, 19555113485,31361954905,101901244565,235103447405, 305354088005,395331063745,600905819065, 608393336905,686701313405,730071885005] |