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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 30 |
| 4 | 161 |
| 5 | 882 |
| 6 | 4916 |
| 7 | 27729 |
| 8 | 157830 |
| 9 | 904706 |
| 10 | 5215310 |
| 11 | 30203901 |
| 12 | 175598997 |
| 13 | 1024234850 |
| 14 | 5990912280 |
| 15 | 35126915550 |
| 16 | 206399581434 |
| 17 | 1215040298106 |
| 18 | 7164651246340 |
| 19 | 42310256416456 |
| 20 | 250194442456101 |
| 21 | 1481274328929984 |
| 22 | 8779528511274564 |
[1,6,30,161,882,4916,27729,157830,904706,5215310, 30203901,175598997,1024234850,5990912280, 35126915550,206399581434,1215040298106, 7164651246340,42310256416456,250194442456101, 1481274328929984,8779528511274564] |