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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 37 |
| 5 | 176 |
| 6 | 979 |
| 7 | 6658 |
| 8 | 50873 |
| 9 | 451180 |
| 10 | 4376911 |
| 11 | 47740694 |
| 12 | 560586613 |
| 13 | 7248848608 |
| 14 | 99837660875 |
| 15 | 1492197903466 |
| 16 | 23571796088689 |
| 17 | 399706304138708 |
| 18 | 7121101849585543 |
| 19 | 135049981967575870 |
| 20 | 2678257990821099821 |
| 21 | 56164666081871350984 |
| 22 | 1226908363217557264003 |
| 23 | 28188326528878836076178 |
[1,1,3,10,37,176,979,6658,50873,451180,4376911, 47740694,560586613,7248848608,99837660875, 1492197903466,23571796088689,399706304138708, 7121101849585543,135049981967575870, 2678257990821099821,56164666081871350984, 1226908363217557264003,28188326528878836076178] |