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| n | a(n) |
|---|---|
| 1 | 56 |
| 2 | 194 |
| 3 | 676 |
| 4 | 2356 |
| 5 | 8210 |
| 6 | 28610 |
| 7 | 99700 |
| 8 | 347434 |
| 9 | 1210736 |
| 10 | 4219166 |
| 11 | 14702926 |
| 12 | 51236674 |
| 13 | 178549274 |
| 14 | 622207508 |
| 15 | 2168265232 |
| 16 | 7555958512 |
| 17 | 26330961818 |
| 18 | 91757987972 |
| 19 | 319757721532 |
| 20 | 1114289913490 |
| 21 | 3883071237050 |
| 22 | 13531704854780 |
[56,194,676,2356,8210,28610,99700,347434,1210736, 4219166,14702926,51236674,178549274,622207508, 2168265232,7555958512,26330961818,91757987972, 319757721532,1114289913490,3883071237050, 13531704854780] |