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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 30 |
| 3 | 135 |
| 4 | 614 |
| 5 | 2799 |
| 6 | 12766 |
| 7 | 58231 |
| 8 | 265622 |
| 9 | 1211647 |
| 10 | 5526990 |
| 11 | 25211655 |
| 12 | 115004294 |
| 13 | 524598159 |
| 14 | 2392982206 |
| 15 | 10915714711 |
| 16 | 49792609142 |
| 17 | 227131616287 |
| 18 | 1036072863150 |
| 19 | 4726101083175 |
| 20 | 21558359689574 |
| 21 | 98339596281519 |
| 22 | 448581262028446 |
[7,30,135,614,2799,12766,58231,265622,1211647, 5526990,25211655,115004294,524598159,2392982206, 10915714711,49792609142,227131616287, 1036072863150,4726101083175,21558359689574, 98339596281519,448581262028446] |