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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 174 |
| 5 | 809 |
| 6 | 3844 |
| 7 | 18453 |
| 8 | 89381 |
| 9 | 435538 |
| 10 | 2132335 |
| 11 | 10476821 |
| 12 | 51621051 |
| 13 | 254914718 |
| 14 | 1261096981 |
| 15 | 6248016875 |
| 16 | 30993074650 |
| 17 | 153896056649 |
| 18 | 764821193488 |
| 19 | 3803687896469 |
| 20 | 18928494638048 |
| 21 | 94244360957085 |
| 22 | 469451989760545 |
| 23 | 2339360937296214 |
| 24 | 11661420918757803 |
| 25 | 58148064857949913 |
| 26 | 290023251544762577 |
[1,2,9,38,174,809,3844,18453,89381,435538,2132335, 10476821,51621051,254914718,1261096981,6248016875, 30993074650,153896056649,764821193488, 3803687896469,18928494638048,94244360957085, 469451989760545,2339360937296214, 11661420918757803,58148064857949913, 290023251544762577] |