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| n | a(n) |
|---|---|
| 1 | 69 |
| 2 | 417 |
| 3 | 2688 |
| 4 | 17406 |
| 5 | 112830 |
| 6 | 731610 |
| 7 | 4743680 |
| 8 | 30758256 |
| 9 | 199437026 |
| 10 | 1293154716 |
| 11 | 8384845368 |
| 12 | 54367536934 |
| 13 | 352520397960 |
| 14 | 2285750623774 |
| 15 | 14820861258700 |
| 16 | 96098815951376 |
| 17 | 623107002046964 |
| 18 | 4040240581140500 |
| 19 | 26197015761022948 |
[69,417,2688,17406,112830,731610,4743680,30758256, 199437026,1293154716,8384845368,54367536934, 352520397960,2285750623774,14820861258700, 96098815951376,623107002046964,4040240581140500, 26197015761022948] |