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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 22 |
| 4 | 81 |
| 5 | 285 |
| 6 | 1339 |
| 7 | 6264 |
| 8 | 33567 |
| 9 | 186811 |
| 10 | 1116105 |
| 11 | 7001244 |
| 12 | 46150265 |
| 13 | 318158826 |
| 14 | 2286494076 |
| 15 | 17088720336 |
| 16 | 132492477111 |
| 17 | 1063527470481 |
| 18 | 8822541504319 |
| 19 | 75512660179788 |
| 20 | 665878308902676 |
| 21 | 6041491458457319 |
| 22 | 56330651731617333 |
| 23 | 539160888285121116 |
| 24 | 5292067580412471801 |
| 25 | 53218232521845617886 |
| 26 | 547833354998854396224 |
| 27 | 5768212264434778469998 |
| 28 | 62074688689939991197548 |
[1,3,9,22,81,285,1339,6264,33567,186811,1116105, 7001244,46150265,318158826,2286494076,17088720336, 132492477111,1063527470481,8822541504319, 75512660179788,665878308902676,6041491458457319, 56330651731617333,539160888285121116, 5292067580412471801,53218232521845617886, 547833354998854396224,5768212264434778469998, 62074688689939991197548] |