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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 32 |
| 4 | 134 |
| 5 | 590 |
| 6 | 2650 |
| 7 | 12064 |
| 8 | 55742 |
| 9 | 259760 |
| 10 | 1220165 |
| 11 | 5767786 |
| 12 | 27395139 |
| 13 | 130723031 |
| 14 | 626095767 |
| 15 | 3007682664 |
| 16 | 14490348210 |
| 17 | 69982637896 |
| 18 | 338693616769 |
| 19 | 1642344787172 |
| 20 | 7977531045463 |
| 21 | 38809381542851 |
| 22 | 189063863417711 |
| 23 | 922205499663732 |
| 24 | 4503486619557610 |
| 25 | 22015401828941826 |
| 26 | 107726338149374056 |
[1,2,8,32,134,590,2650,12064,55742,259760,1220165, 5767786,27395139,130723031,626095767,3007682664, 14490348210,69982637896,338693616769, 1642344787172,7977531045463,38809381542851, 189063863417711,922205499663732,4503486619557610, 22015401828941826,107726338149374056] |