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| n | a(n) |
|---|---|
| 0 | 5 |
| 1 | 9 |
| 2 | 23 |
| 3 | 55 |
| 4 | 133 |
| 5 | 321 |
| 6 | 775 |
| 7 | 1871 |
| 8 | 4517 |
| 9 | 10905 |
| 10 | 26327 |
| 11 | 63559 |
| 12 | 153445 |
| 13 | 370449 |
| 14 | 894343 |
| 15 | 2159135 |
| 16 | 5212613 |
| 17 | 12584361 |
| 18 | 30381335 |
| 19 | 73347031 |
| 20 | 177075397 |
| 21 | 427497825 |
| 22 | 1032071047 |
| 23 | 2491639919 |
| 24 | 6015350885 |
| 25 | 14522341689 |
| 26 | 35060034263 |
| 27 | 84642410215 |
[5,9,23,55,133,321,775,1871,4517,10905,26327, 63559,153445,370449,894343,2159135,5212613, 12584361,30381335,73347031,177075397,427497825, 1032071047,2491639919,6015350885,14522341689, 35060034263,84642410215] |