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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 5 |
| 5 | 17 |
| 6 | 89 |
| 7 | 211 |
| 8 | 1903 |
| 9 | 62473 |
| 10 | 89393 |
| 11 | 1324937 |
| 12 | 199986173 |
| 13 | 1248315547 |
| 14 | 25821989299 |
| 15 | 1754517215113 |
| 16 | 1308752009069 |
| 17 | 34794177047129 |
| 18 | 32791050165840089 |
| 19 | 37082480057069939 |
| 20 | 109598046569166901 |
| 21 | 7850794626671440751 |
| 22 | 1049848025022301180127 |
| 23 | 47709314255406993620857 |
[1,1,2,3,5,17,89,211,1903,62473,89393,1324937, 199986173,1248315547,25821989299,1754517215113, 1308752009069,34794177047129,32791050165840089, 37082480057069939,109598046569166901, 7850794626671440751,1049848025022301180127, 47709314255406993620857] |