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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 12 |
| 4 | 5 |
| 5 | 33 |
| 6 | 55 |
| 7 | 132 |
| 8 | 272 |
| 9 | 630 |
| 10 | 1355 |
| 11 | 3010 |
| 12 | 6661 |
| 13 | 14688 |
| 14 | 32563 |
| 15 | 71941 |
| 16 | 159408 |
| 17 | 352601 |
| 18 | 781046 |
| 19 | 1728906 |
| 20 | 3829080 |
| 21 | 8478988 |
| 22 | 18778735 |
| 23 | 41589469 |
| 24 | 92113712 |
| 25 | 204020792 |
| 26 | 451891357 |
| 27 | 1000927728 |
| 28 | 2217056520 |
| 29 | 4910855519 |
| 30 | 10877806629 |
[1,1,12,5,33,55,132,272,630,1355,3010,6661,14688, 32563,71941,159408,352601,781046,1728906,3829080, 8478988,18778735,41589469,92113712,204020792, 451891357,1000927728,2217056520,4910855519, 10877806629] |