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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 13 |
| 3 | 61 |
| 4 | 263 |
| 5 | 1094 |
| 6 | 4578 |
| 7 | 18076 |
| 8 | 69815 |
| 9 | 262242 |
| 10 | 965342 |
| 11 | 3480006 |
| 12 | 12322360 |
| 13 | 42896002 |
| 14 | 147062818 |
| 15 | 497000146 |
| 16 | 1657470977 |
| 17 | 5459160063 |
| 18 | 17772284155 |
| 19 | 57225458626 |
| 20 | 182362100816 |
| 21 | 575463112191 |
| 22 | 1799106136923 |
| 23 | 5575063264825 |
| 24 | 17130798464652 |
| 25 | 52216240087807 |
| 26 | 157937816918539 |
| 27 | 474197830869573 |
| 28 | 1413695306175884 |
| 29 | 4185962563381518 |
[1,1,13,61,263,1094,4578,18076,69815,262242, 965342,3480006,12322360,42896002,147062818, 497000146,1657470977,5459160063,17772284155, 57225458626,182362100816,575463112191, 1799106136923,5575063264825,17130798464652, 52216240087807,157937816918539,474197830869573, 1413695306175884,4185962563381518] |