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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 47 |
| 4 | 150 |
| 5 | 797 |
| 6 | 3338 |
| 7 | 7473 |
| 8 | 451718 |
| 9 | 910909 |
| 10 | 4095354 |
| 11 | 21387679 |
| 12 | 68258391 |
| 13 | 362679634 |
| 14 | 1518976927 |
| 15 | 3400633488 |
| 16 | 205556986207 |
| 17 | 414514605902 |
| 18 | 1863615409815 |
| 19 | 9732591654977 |
| 20 | 31061390374746 |
| 21 | 165039543528707 |
| 22 | 691219564489574 |
| 23 | 1547478672507855 |
| 24 | 93539939914960874 |
[1,2,9,47,150,797,3338,7473,451718,910909,4095354, 21387679,68258391,362679634,1518976927,3400633488, 205556986207,414514605902,1863615409815, 9732591654977,31061390374746,165039543528707, 691219564489574,1547478672507855, 93539939914960874] |