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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 127 |
| 3 | 967 |
| 4 | 5509 |
| 5 | 23425 |
| 6 | 101567 |
| 7 | 438177 |
| 8 | 1895197 |
| 9 | 8198571 |
| 10 | 35463355 |
| 11 | 153408903 |
| 12 | 663650521 |
| 13 | 2870932567 |
| 14 | 12419542739 |
| 15 | 53726653631 |
| 16 | 232420358051 |
| 17 | 1005444905517 |
| 18 | 4349531110857 |
| 19 | 18815972516807 |
| 20 | 81397465699935 |
| 21 | 352123564686167 |
[13,127,967,5509,23425,101567,438177,1895197, 8198571,35463355,153408903,663650521,2870932567, 12419542739,53726653631,232420358051, 1005444905517,4349531110857,18815972516807, 81397465699935,352123564686167] |