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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 9 |
| 4 | 45 |
| 5 | 121 |
| 6 | 509 |
| 7 | 1745 |
| 8 | 6565 |
| 9 | 25473 |
| 10 | 95333 |
| 11 | 377369 |
| 12 | 1466925 |
| 13 | 5767385 |
| 14 | 23131709 |
| 15 | 91583241 |
| 16 | 369636245 |
| 17 | 1489745457 |
| 18 | 6019414749 |
| 19 | 24561243097 |
| 20 | 99915769557 |
| 21 | 409006211521 |
| 22 | 1680181737581 |
| 23 | 6897520420113 |
| 24 | 28491147830797 |
| 25 | 117644375606081 |
| 26 | 486929303998637 |
| 27 | 2022669691473049 |
| 28 | 8395994639957741 |
[1,1,5,9,45,121,509,1745,6565,25473,95333,377369, 1466925,5767385,23131709,91583241,369636245, 1489745457,6019414749,24561243097,99915769557, 409006211521,1680181737581,6897520420113, 28491147830797,117644375606081,486929303998637, 2022669691473049,8395994639957741] |