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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 61 |
| 3 | 323 |
| 4 | 1759 |
| 5 | 9593 |
| 6 | 52401 |
| 7 | 286207 |
| 8 | 1563111 |
| 9 | 8536807 |
| 10 | 46623423 |
| 11 | 254632457 |
| 12 | 1390667451 |
| 13 | 7595086541 |
| 14 | 41480325457 |
| 15 | 226543492197 |
| 16 | 1237260160029 |
| 17 | 6757257460559 |
| 18 | 36904549131343 |
| 19 | 201553034567103 |
| 20 | 1100775560224471 |
[9,61,323,1759,9593,52401,286207,1563111,8536807, 46623423,254632457,1390667451,7595086541, 41480325457,226543492197,1237260160029, 6757257460559,36904549131343,201553034567103, 1100775560224471] |