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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 42 |
| 4 | 211 |
| 5 | 1058 |
| 6 | 5292 |
| 7 | 26461 |
| 8 | 132308 |
| 9 | 661542 |
| 10 | 3307711 |
| 11 | 16538558 |
| 12 | 82692792 |
| 13 | 413463961 |
| 14 | 2067319808 |
| 15 | 10336599042 |
| 16 | 51682995211 |
| 17 | 258414976058 |
| 18 | 1292074880292 |
| 19 | 6460374401461 |
| 20 | 32301872007308 |
| 21 | 161509360036542 |
| 22 | 807546800182711 |
[1,8,42,211,1058,5292,26461,132308,661542,3307711, 16538558,82692792,413463961,2067319808, 10336599042,51682995211,258414976058, 1292074880292,6460374401461,32301872007308, 161509360036542,807546800182711] |