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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 36 |
| 3 | 216 |
| 4 | 1096 |
| 5 | 4504 |
| 6 | 17986 |
| 7 | 71278 |
| 8 | 287154 |
| 9 | 1174282 |
| 10 | 4842316 |
| 11 | 20019620 |
| 12 | 82713844 |
| 13 | 341336666 |
| 14 | 1407252850 |
| 15 | 5799332126 |
| 16 | 23897370232 |
| 17 | 98480668292 |
| 18 | 405872225912 |
| 19 | 1672825694744 |
| 20 | 6894787036372 |
| 21 | 28417852764586 |
| 22 | 117127559374180 |
[6,36,216,1096,4504,17986,71278,287154,1174282, 4842316,20019620,82713844,341336666,1407252850, 5799332126,23897370232,98480668292,405872225912, 1672825694744,6894787036372,28417852764586, 117127559374180] |