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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 42 |
| 4 | 210 |
| 5 | 1051 |
| 6 | 5258 |
| 7 | 26292 |
| 8 | 131460 |
| 9 | 657301 |
| 10 | 3286508 |
| 11 | 16432542 |
| 12 | 82162710 |
| 13 | 410813551 |
| 14 | 2054067758 |
| 15 | 10270338792 |
| 16 | 51351693960 |
| 17 | 256758469801 |
| 18 | 1283792349008 |
| 19 | 6418961745042 |
| 20 | 32094808725210 |
| 21 | 160474043626051 |
| 22 | 802370218130258 |
[1,8,42,210,1051,5258,26292,131460,657301,3286508, 16432542,82162710,410813551,2054067758, 10270338792,51351693960,256758469801, 1283792349008,6418961745042,32094808725210, 160474043626051,802370218130258] |