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| n | a(n) |
|---|---|
| 1 | 30 |
| 2 | 111 |
| 3 | 423 |
| 4 | 1611 |
| 5 | 6132 |
| 6 | 23340 |
| 7 | 88839 |
| 8 | 338148 |
| 9 | 1287093 |
| 10 | 4899063 |
| 11 | 18647307 |
| 12 | 70977258 |
| 13 | 270160788 |
| 14 | 1028313201 |
| 15 | 3914069274 |
| 16 | 14898124683 |
| 17 | 56706742659 |
| 18 | 215842915227 |
| 19 | 821563042932 |
| 20 | 3127115999160 |
| 21 | 11902743868935 |
| 22 | 45305422519512 |
[30,111,423,1611,6132,23340,88839,338148,1287093, 4899063,18647307,70977258,270160788,1028313201, 3914069274,14898124683,56706742659,215842915227, 821563042932,3127115999160,11902743868935, 45305422519512] |