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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 171 |
| 3 | 171 |
| 4 | 405 |
| 5 | 1773 |
| 6 | 405 |
| 7 | 3249 |
| 8 | 20097 |
| 9 | 20097 |
| 10 | 3249 |
| 11 | 12609 |
| 12 | 222003 |
| 13 | 424197 |
| 14 | 222003 |
| 15 | 12609 |
| 16 | 72225 |
| 17 | 2506851 |
| 18 | 10670517 |
| 19 | 10670517 |
| 20 | 2506851 |
| 21 | 72225 |
| 22 | 332937 |
| 23 | 28276065 |
| 24 | 254648349 |
| 25 | 560733777 |
| 26 | 254648349 |
| 27 | 28276065 |
| 28 | 332937 |
| 29 | 1731321 |
| 30 | 319126401 |
[0,171,171,405,1773,405,3249,20097,20097,3249, 12609,222003,424197,222003,12609,72225,2506851, 10670517,10670517,2506851,72225,332937,28276065, 254648349,560733777,254648349,28276065,332937, 1731321,319126401] |