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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 11 |
| 5 | 28 |
| 6 | 105 |
| 7 | 362 |
| 8 | 1093 |
| 9 | 3659 |
| 10 | 13001 |
| 11 | 45171 |
| 12 | 159510 |
| 13 | 563833 |
| 14 | 2008295 |
| 15 | 7333827 |
| 16 | 26730538 |
| 17 | 97256891 |
| 18 | 358079458 |
| 19 | 1324674524 |
| 20 | 4902380577 |
[1,1,5,11,28,105,362,1093,3659,13001,45171,159510, 563833,2008295,7333827,26730538,97256891, 358079458,1324674524,4902380577] |