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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 23 |
| 5 | 71 |
| 6 | 241 |
| 7 | 827 |
| 8 | 2969 |
| 9 | 10719 |
| 10 | 39869 |
| 11 | 149412 |
| 12 | 568421 |
| 13 | 2188494 |
| 14 | 8488370 |
| 15 | 33235585 |
| 16 | 131138445 |
| 17 | 520203906 |
| 18 | 2078395161 |
| 19 | 8342877038 |
| 20 | 33647604003 |
| 21 | 136384448249 |
| 22 | 554714145737 |
| 23 | 2265211261374 |
| 24 | 9282805581252 |
| 25 | 38149282176628 |
| 26 | 157293038322763 |
| 27 | 650217712657603 |
| 28 | 2694590903013221 |
[1,1,3,7,23,71,241,827,2969,10719,39869,149412, 568421,2188494,8488370,33235585,131138445, 520203906,2078395161,8342877038,33647604003, 136384448249,554714145737,2265211261374, 9282805581252,38149282176628,157293038322763, 650217712657603,2694590903013221] |