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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 13 |
| 3 | 58 |
| 4 | 268 |
| 5 | 1274 |
| 6 | 6103 |
| 7 | 29578 |
| 8 | 144191 |
| 9 | 706114 |
| 10 | 3471529 |
| 11 | 17111174 |
| 12 | 84533573 |
| 13 | 418347563 |
| 14 | 2073295781 |
| 15 | 10287239649 |
| 16 | 51092700553 |
| 17 | 253964860179 |
| 18 | 1263247273324 |
| 19 | 6287222042418 |
| 20 | 31307431744880 |
| 21 | 155964283770448 |
| 22 | 777259889839215 |
| 23 | 3874804737467137 |
| 24 | 19322276999093931 |
| 25 | 96377663750354783 |
[1,3,13,58,268,1274,6103,29578,144191,706114, 3471529,17111174,84533573,418347563,2073295781, 10287239649,51092700553,253964860179, 1263247273324,6287222042418,31307431744880, 155964283770448,777259889839215,3874804737467137, 19322276999093931,96377663750354783] |