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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 43 |
| 5 | 187 |
| 6 | 859 |
| 7 | 4059 |
| 8 | 19419 |
| 9 | 93403 |
| 10 | 450267 |
| 11 | 2172635 |
| 12 | 10487515 |
| 13 | 50632411 |
| 14 | 244463323 |
| 15 | 1180350171 |
| 16 | 5699188443 |
| 17 | 27518023387 |
| 18 | 132868585179 |
| 19 | 641545909979 |
| 20 | 3097656932059 |
| 21 | 14956809271003 |
| 22 | 72217860617947 |
| 23 | 348698671167195 |
[0,1,3,11,43,187,859,4059,19419,93403,450267, 2172635,10487515,50632411,244463323,1180350171, 5699188443,27518023387,132868585179,641545909979, 3097656932059,14956809271003,72217860617947, 348698671167195] |