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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 99 |
| 3 | 1618 |
| 4 | 28051 |
| 5 | 502182 |
| 6 | 9174174 |
| 7 | 169955268 |
| 8 | 3180814851 |
| 9 | 59997194782 |
| 10 | 1138669104874 |
| 11 | 21718428172668 |
| 12 | 415955669988526 |
| 13 | 7994062687411132 |
| 14 | 154087546950639324 |
| 15 | 2977629771383522568 |
| 16 | 57667991491752308451 |
| 17 | 1119034767346120619982 |
| 18 | 21752068061568290996274 |
[1,7,99,1618,28051,502182,9174174,169955268, 3180814851,59997194782,1138669104874, 21718428172668,415955669988526,7994062687411132, 154087546950639324,2977629771383522568, 57667991491752308451,1119034767346120619982, 21752068061568290996274] |