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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 13 |
| 3 | 55 |
| 4 | 221 |
| 5 | 887 |
| 6 | 3549 |
| 7 | 14199 |
| 8 | 56797 |
| 9 | 227191 |
| 10 | 908765 |
| 11 | 3635063 |
| 12 | 14540253 |
| 13 | 58161015 |
| 14 | 232644061 |
| 15 | 930576247 |
| 16 | 3722304989 |
| 17 | 14889219959 |
| 18 | 59556879837 |
| 19 | 238227519351 |
| 20 | 952910077405 |
| 21 | 3811640309623 |
| 22 | 15246561238493 |
| 23 | 60986244953975 |
[3,13,55,221,887,3549,14199,56797,227191,908765, 3635063,14540253,58161015,232644061,930576247, 3722304989,14889219959,59556879837,238227519351, 952910077405,3811640309623,15246561238493, 60986244953975] |