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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 18 |
| 4 | 86 |
| 5 | 389 |
| 6 | 1681 |
| 7 | 7096 |
| 8 | 29484 |
| 9 | 121227 |
| 10 | 494759 |
| 11 | 2008574 |
| 12 | 8122882 |
| 13 | 32757265 |
| 14 | 131826237 |
| 15 | 529696452 |
| 16 | 2125960280 |
| 17 | 8525364503 |
| 18 | 34166028115 |
| 19 | 136857822730 |
| 20 | 548012421678 |
| 21 | 2193793078941 |
| 22 | 8780402492393 |
| 23 | 35137300499408 |
| 24 | 140596273587076 |
| 25 | 562526309116579 |
[1,3,18,86,389,1681,7096,29484,121227,494759, 2008574,8122882,32757265,131826237,529696452, 2125960280,8525364503,34166028115,136857822730, 548012421678,2193793078941,8780402492393, 35137300499408,140596273587076,562526309116579] |