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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 97 |
| 5 | 961 |
| 6 | 10201 |
| 7 | 177241 |
| 8 | 3801505 |
| 9 | 80718625 |
| 10 | 1887205681 |
| 11 | 52896262321 |
| 12 | 1648697978401 |
| 13 | 54216677033377 |
| 14 | 1928791931034697 |
| 15 | 75326014326206281 |
| 16 | 3159713152034201281 |
| 17 | 140373558362282197441 |
| 18 | 6632746205445950124385 |
| 19 | 333591744669464008432225 |
[1,1,1,7,97,961,10201,177241,3801505,80718625, 1887205681,52896262321,1648697978401, 54216677033377,1928791931034697,75326014326206281, 3159713152034201281,140373558362282197441, 6632746205445950124385,333591744669464008432225] |