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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 11 |
| 5 | 19 |
| 6 | 31 |
| 7 | 79 |
| 8 | 211 |
| 9 | 607 |
| 10 | 1931 |
| 11 | 6337 |
| 12 | 21961 |
| 13 | 78919 |
| 14 | 295291 |
| 15 | 1143563 |
| 16 | 4574149 |
| 17 | 18859777 |
| 18 | 80014843 |
| 19 | 348776611 |
| 20 | 1559776279 |
| 21 | 7147792903 |
| 22 | 33526120129 |
| 23 | 160785623729 |
| 24 | 787685471519 |
| 25 | 3938427356629 |
| 26 | 20082117944579 |
| 27 | 104349745809137 |
| 28 | 552166953567737 |
[2,2,3,11,19,31,79,211,607,1931,6337,21961,78919, 295291,1143563,4574149,18859777,80014843, 348776611,1559776279,7147792903,33526120129, 160785623729,787685471519,3938427356629, 20082117944579,104349745809137,552166953567737] |