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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 107 |
| 5 | 947 |
| 6 | 10399 |
| 7 | 135151 |
| 8 | 2027033 |
| 9 | 34459429 |
| 10 | 654729139 |
| 11 | 13749310577 |
| 12 | 316234143227 |
| 13 | 7905853580633 |
| 14 | 213458046676877 |
| 15 | 6190283353629379 |
| 16 | 191898783962510743 |
| 17 | 6332659870762850657 |
| 18 | 221643095476699771957 |
| 19 | 8200794532637891559553 |
| 20 | 319830986772877770815629 |
[2,5,17,107,947,10399,135151,2027033,34459429, 654729139,13749310577,316234143227,7905853580633, 213458046676877,6190283353629379, 191898783962510743,6332659870762850657, 221643095476699771957,8200794532637891559553, 319830986772877770815629] |