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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 32 |
| 4 | 138 |
| 5 | 612 |
| 6 | 2782 |
| 7 | 12835 |
| 8 | 59916 |
| 9 | 282151 |
| 10 | 1337920 |
| 11 | 6379086 |
| 12 | 30552956 |
| 13 | 146880837 |
| 14 | 708342744 |
| 15 | 3425171883 |
| 16 | 16600524520 |
| 17 | 80617576576 |
| 18 | 392192150420 |
| 19 | 1910910968991 |
| 20 | 9323518359408 |
| 21 | 45546419600056 |
| 22 | 222746154981758 |
| 23 | 1090440406459158 |
| 24 | 5343057270195160 |
| 25 | 26202306700463284 |
| 26 | 128594087415902160 |
[1,2,8,32,138,612,2782,12835,59916,282151,1337920, 6379086,30552956,146880837,708342744,3425171883, 16600524520,80617576576,392192150420, 1910910968991,9323518359408,45546419600056, 222746154981758,1090440406459158,5343057270195160, 26202306700463284,128594087415902160] |