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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 7 |
| 3 | 19 |
| 4 | 91 |
| 5 | 331 |
| 6 | 1387 |
| 7 | 5419 |
| 8 | 21931 |
| 9 | 87211 |
| 10 | 349867 |
| 11 | 1397419 |
| 12 | 5593771 |
| 13 | 22366891 |
| 14 | 89483947 |
| 15 | 357903019 |
| 16 | 1431677611 |
| 17 | 5726579371 |
| 18 | 22906579627 |
| 19 | 91625794219 |
| 20 | 366504225451 |
| 21 | 1466014804651 |
| 22 | 5864063412907 |
| 23 | 23456245263019 |
| 24 | 93824997829291 |
| 25 | 375299957762731 |
[1,1,7,19,91,331,1387,5419,21931,87211,349867, 1397419,5593771,22366891,89483947,357903019, 1431677611,5726579371,22906579627,91625794219, 366504225451,1466014804651,5864063412907, 23456245263019,93824997829291,375299957762731] |