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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 13 |
| 3 | 70 |
| 4 | 429 |
| 5 | 2842 |
| 6 | 19794 |
| 7 | 142758 |
| 8 | 1056655 |
| 9 | 7980280 |
| 10 | 61251261 |
| 11 | 476387379 |
| 12 | 3746317414 |
| 13 | 29738316330 |
| 14 | 237968639936 |
| 15 | 1917578268288 |
| 16 | 15546796822656 |
| 17 | 126728260011920 |
| 18 | 1037987924978125 |
| 19 | 8538459191677170 |
| 20 | 70509828893263474 |
| 21 | 584310452973463242 |
| 22 | 4857624566855734836 |
| 23 | 40501472981905806550 |
| 24 | 338594135314564168494 |
| 25 | 2837641019938074131463 |
| 26 | 23835438376045780734390 |
| 27 | 200633658871150345742269 |
| 28 | 1692132786239339256115050 |
| 29 | 14297391426538004065333910 |
| 30 | 121009206594941545408186768 |
[1,3,13,70,429,2842,19794,142758,1056655,7980280, 61251261,476387379,3746317414,29738316330, 237968639936,1917578268288,15546796822656, 126728260011920,1037987924978125,8538459191677170, 70509828893263474,584310452973463242, 4857624566855734836,40501472981905806550, 338594135314564168494,2837641019938074131463, 23835438376045780734390,200633658871150345742269, 1692132786239339256115050, 14297391426538004065333910, 121009206594941545408186768] |