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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 31 |
| 3 | 21 |
| 4 | 77 |
| 5 | 348 |
| 6 | 1094 |
| 7 | 3919 |
| 8 | 13977 |
| 9 | 49728 |
| 10 | 182756 |
| 11 | 669766 |
| 12 | 2444078 |
| 13 | 8944985 |
| 14 | 32753763 |
| 15 | 119833236 |
| 16 | 438741809 |
| 17 | 1606516717 |
| 18 | 5881961826 |
| 19 | 21538299550 |
| 20 | 78868479665 |
| 21 | 288794128838 |
| 22 | 1057512050898 |
| 23 | 3872421498652 |
| 24 | 14180120799422 |
[1,31,21,77,348,1094,3919,13977,49728,182756, 669766,2444078,8944985,32753763,119833236, 438741809,1606516717,5881961826,21538299550, 78868479665,288794128838,1057512050898, 3872421498652,14180120799422] |