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| n | a(n) |
|---|---|
| 1 | 17 |
| 2 | 80 |
| 3 | 388 |
| 4 | 1872 |
| 5 | 9040 |
| 6 | 43648 |
| 7 | 210752 |
| 8 | 1017600 |
| 9 | 4913408 |
| 10 | 23724032 |
| 11 | 114549760 |
| 12 | 553095168 |
| 13 | 2670579712 |
| 14 | 12894699520 |
| 15 | 62261116928 |
| 16 | 300623265792 |
| 17 | 1451537530880 |
| 18 | 7008643186688 |
| 19 | 33840722870272 |
| 20 | 163397464227840 |
| 21 | 788952748392448 |
| 22 | 3809400850481152 |
[17,80,388,1872,9040,43648,210752,1017600,4913408, 23724032,114549760,553095168,2670579712, 12894699520,62261116928,300623265792, 1451537530880,7008643186688,33840722870272, 163397464227840,788952748392448,3809400850481152] |