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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 14 |
| 4 | 46 |
| 5 | 154 |
| 6 | 578 |
| 7 | 2056 |
| 8 | 7734 |
| 9 | 29832 |
| 10 | 113786 |
| 11 | 448286 |
| 12 | 1762158 |
| 13 | 6982215 |
| 14 | 28034055 |
| 15 | 112599212 |
| 16 | 456160196 |
| 17 | 1855679003 |
| 18 | 7575193160 |
| 19 | 31073949234 |
| 20 | 127882427241 |
| 21 | 528025970306 |
| 22 | 2186615978962 |
| 23 | 9081877366235 |
| 24 | 37801377197439 |
| 25 | 157763676455239 |
| 26 | 659823092941944 |
| 27 | 2764674164214323 |
[1,2,4,14,46,154,578,2056,7734,29832,113786, 448286,1762158,6982215,28034055,112599212, 456160196,1855679003,7575193160,31073949234, 127882427241,528025970306,2186615978962, 9081877366235,37801377197439,157763676455239, 659823092941944,2764674164214323] |