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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 16 |
| 5 | 93 |
| 6 | 668 |
| 7 | 3440 |
| 8 | 13728 |
| 9 | 46252 |
| 10 | 172577 |
| 11 | 739002 |
| 12 | 3417464 |
| 13 | 15550336 |
| 14 | 65956764 |
| 15 | 271247405 |
| 16 | 1119519052 |
| 17 | 4726308568 |
| 18 | 20348072952 |
| 19 | 87598217268 |
| 20 | 373660404281 |
| 21 | 1581318625634 |
| 22 | 6680851858676 |
| 23 | 28326586367464 |
| 24 | 120536842633616 |
| 25 | 513461699313993 |
[1,2,4,8,16,93,668,3440,13728,46252,172577,739002, 3417464,15550336,65956764,271247405,1119519052, 4726308568,20348072952,87598217268,373660404281, 1581318625634,6680851858676,28326586367464, 120536842633616,513461699313993] |