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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 32 |
| 5 | 80 |
| 6 | 208 |
| 7 | 560 |
| 8 | 1552 |
| 9 | 4144 |
| 10 | 11152 |
| 11 | 30128 |
| 12 | 81424 |
| 13 | 219440 |
| 14 | 592016 |
| 15 | 1597616 |
| 16 | 4310800 |
| 17 | 11629616 |
| 18 | 31377808 |
| 19 | 84661168 |
| 20 | 228421648 |
| 21 | 616292144 |
| 22 | 1662802576 |
| 23 | 4486362800 |
| 24 | 12104509712 |
| 25 | 32658782768 |
| 26 | 88115674000 |
| 27 | 237742180784 |
[1,2,4,8,32,80,208,560,1552,4144,11152,30128, 81424,219440,592016,1597616,4310800,11629616, 31377808,84661168,228421648,616292144,1662802576, 4486362800,12104509712,32658782768,88115674000, 237742180784] |