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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 12 |
| 3 | 49 |
| 4 | 224 |
| 5 | 1003 |
| 6 | 4795 |
| 7 | 22343 |
| 8 | 108701 |
| 9 | 517169 |
| 10 | 2539693 |
| 11 | 12239287 |
| 12 | 60428125 |
| 13 | 293673869 |
| 14 | 1454899827 |
| 15 | 7112278267 |
| 16 | 35315525591 |
| 17 | 173378316769 |
| 18 | 862262869950 |
| 19 | 4246791976980 |
| 20 | 21144661336751 |
| 21 | 104398733451674 |
| 22 | 520236235063489 |
| 23 | 2573592946206401 |
| 24 | 12832805881033345 |
| 25 | 63582494681839206 |
| 26 | 317199347679668932 |
[1,3,12,49,224,1003,4795,22343,108701,517169, 2539693,12239287,60428125,293673869,1454899827, 7112278267,35315525591,173378316769,862262869950, 4246791976980,21144661336751,104398733451674, 520236235063489,2573592946206401, 12832805881033345,63582494681839206, 317199347679668932] |