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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 176 |
| 5 | 823 |
| 6 | 3923 |
| 7 | 18896 |
| 8 | 91764 |
| 9 | 447969 |
| 10 | 2197018 |
| 11 | 10808493 |
| 12 | 53314066 |
| 13 | 263518119 |
| 14 | 1304635500 |
| 15 | 6467863885 |
| 16 | 32100843512 |
| 17 | 159468346798 |
| 18 | 792819418523 |
| 19 | 3944217414510 |
| 20 | 19633286243766 |
| 21 | 97776890309758 |
| 22 | 487148147762393 |
| 23 | 2427973454113814 |
| 24 | 12104993886409944 |
| 25 | 60367867058622098 |
| 26 | 301129528117164483 |
[1,2,9,38,176,823,3923,18896,91764,447969,2197018, 10808493,53314066,263518119,1304635500,6467863885, 32100843512,159468346798,792819418523, 3944217414510,19633286243766,97776890309758, 487148147762393,2427973454113814, 12104993886409944,60367867058622098, 301129528117164483] |