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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 13 |
| 5 | 36 |
| 6 | 110 |
| 7 | 367 |
| 8 | 1243 |
| 9 | 4266 |
| 10 | 14979 |
| 11 | 54636 |
| 12 | 199011 |
| 13 | 734030 |
| 14 | 2756839 |
| 15 | 10450319 |
| 16 | 39836796 |
| 17 | 153059496 |
| 18 | 593960500 |
| 19 | 2316916479 |
| 20 | 9077686257 |
| 21 | 35778018898 |
| 22 | 141845770750 |
| 23 | 564450779427 |
| 24 | 2253100544758 |
| 25 | 9036652220948 |
| 26 | 36388658308498 |
| 27 | 146848107101360 |
| 28 | 594357667427186 |
| 29 | 2414872472739607 |
[1,1,2,4,13,36,110,367,1243,4266,14979,54636, 199011,734030,2756839,10450319,39836796,153059496, 593960500,2316916479,9077686257,35778018898, 141845770750,564450779427,2253100544758, 9036652220948,36388658308498,146848107101360, 594357667427186,2414872472739607] |