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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 8 |
| 4 | 34 |
| 5 | 87 |
| 6 | 383 |
| 7 | 1117 |
| 8 | 5028 |
| 9 | 15912 |
| 10 | 72724 |
| 11 | 243439 |
| 12 | 1124981 |
| 13 | 3923900 |
| 14 | 18286061 |
| 15 | 65823449 |
| 16 | 308779801 |
| 17 | 1139618569 |
| 18 | 5374534823 |
| 19 | 20243260284 |
| 20 | 95889093762 |
| 21 | 367320084707 |
| 22 | 1746361728469 |
| 23 | 6785937114153 |
| 24 | 32364037611038 |
| 25 | 127307351107630 |
| 26 | 608810321451924 |
| 27 | 2420383751811660 |
| 28 | 11602122458266089 |
[1,1,4,8,34,87,383,1117,5028,15912,72724,243439, 1124981,3923900,18286061,65823449,308779801, 1139618569,5374534823,20243260284,95889093762, 367320084707,1746361728469,6785937114153, 32364037611038,127307351107630,608810321451924, 2420383751811660,11602122458266089] |