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| n | a(n) |
|---|---|
| 1 | 80 |
| 2 | 140 |
| 3 | 252 |
| 4 | 462 |
| 5 | 884 |
| 6 | 1684 |
| 7 | 3200 |
| 8 | 6216 |
| 9 | 11944 |
| 10 | 22810 |
| 11 | 44396 |
| 12 | 85402 |
| 13 | 163204 |
| 14 | 317716 |
| 15 | 611248 |
| 16 | 1168198 |
| 17 | 2274196 |
| 18 | 4375320 |
| 19 | 8362052 |
| 20 | 16278784 |
| 21 | 31318664 |
| 22 | 59855842 |
| 23 | 116523764 |
| 24 | 224179214 |
| 25 | 428448488 |
| 26 | 834077068 |
| 27 | 1604674164 |
| 28 | 3066832822 |
[80,140,252,462,884,1684,3200,6216,11944,22810, 44396,85402,163204,317716,611248,1168198,2274196, 4375320,8362052,16278784,31318664,59855842, 116523764,224179214,428448488,834077068, 1604674164,3066832822] |