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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 21 |
| 3 | 73 |
| 4 | 326 |
| 5 | 1376 |
| 6 | 6205 |
| 7 | 28942 |
| 8 | 135093 |
| 9 | 636475 |
| 10 | 3024792 |
| 11 | 14429369 |
| 12 | 69010353 |
| 13 | 330906118 |
| 14 | 1589431389 |
| 15 | 7642628408 |
| 16 | 36779710534 |
| 17 | 177110221193 |
| 18 | 853219818189 |
| 19 | 4111568990816 |
| 20 | 19817506062480 |
| 21 | 95533854083563 |
| 22 | 460587995304966 |
[8,21,73,326,1376,6205,28942,135093,636475, 3024792,14429369,69010353,330906118,1589431389, 7642628408,36779710534,177110221193,853219818189, 4111568990816,19817506062480,95533854083563, 460587995304966] |