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| n | a(n) |
|---|---|
| 1 | 80 |
| 2 | 272 |
| 3 | 856 |
| 4 | 2896 |
| 5 | 9192 |
| 6 | 31064 |
| 7 | 98696 |
| 8 | 333456 |
| 9 | 1059616 |
| 10 | 3579832 |
| 11 | 11375904 |
| 12 | 38432120 |
| 13 | 122129480 |
| 14 | 412598472 |
| 15 | 1311156208 |
| 16 | 4429566640 |
| 17 | 14076290136 |
| 18 | 47554864016 |
| 19 | 151120001288 |
| 20 | 510538698456 |
| 21 | 1622391563368 |
| 22 | 5481032709232 |
[80,272,856,2896,9192,31064,98696,333456,1059616, 3579832,11375904,38432120,122129480,412598472, 1311156208,4429566640,14076290136,47554864016, 151120001288,510538698456,1622391563368, 5481032709232] |