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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 3 |
| 3 | 10 |
| 4 | 42 |
| 5 | 198 |
| 6 | 1001 |
| 7 | 5304 |
| 8 | 29070 |
| 9 | 163438 |
| 10 | 937365 |
| 11 | 5462730 |
| 12 | 32256120 |
| 13 | 192565800 |
| 14 | 1160346492 |
| 15 | 7048030544 |
| 16 | 43108428198 |
| 17 | 265276342782 |
| 18 | 1641229898525 |
| 19 | 10202773534590 |
| 20 | 63698396932170 |
| 21 | 399223286267190 |
| 22 | 2510857763851185 |
| 23 | 15842014607109600 |
| 24 | 100244747986099080 |
[3,3,10,42,198,1001,5304,29070,163438,937365, 5462730,32256120,192565800,1160346492,7048030544, 43108428198,265276342782,1641229898525, 10202773534590,63698396932170,399223286267190, 2510857763851185,15842014607109600, 100244747986099080] |