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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 25 |
| 5 | 193 |
| 6 | 1061 |
| 7 | 19265 |
| 8 | 384413 |
| 9 | 13738057 |
| 10 | 820631045 |
| 11 | 59715152817 |
| 12 | 7053435949925 |
| 13 | 1320192686294957 |
| 14 | 358386777091843317 |
[1,1,1,25,193,1061,19265,384413,13738057, 820631045,59715152817,7053435949925, 1320192686294957,358386777091843317] |