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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 26 |
| 6 | 60 |
| 7 | 132 |
| 8 | 292 |
| 9 | 652 |
| 10 | 1448 |
| 11 | 3216 |
| 12 | 7152 |
| 13 | 15896 |
| 14 | 35328 |
| 15 | 78528 |
| 16 | 174544 |
| 17 | 387952 |
| 18 | 862304 |
| 19 | 1916640 |
| 20 | 4260096 |
| 21 | 9468896 |
| 22 | 21046464 |
| 23 | 46779840 |
| 24 | 103977280 |
| 25 | 231109696 |
| 26 | 513686144 |
| 27 | 1141767168 |
| 28 | 2537799168 |
| 29 | 5640751232 |
| 30 | 12537664512 |
| 31 | 27867393024 |
| 32 | 61940690176 |
[1,1,2,6,12,26,60,132,292,652,1448,3216,7152, 15896,35328,78528,174544,387952,862304,1916640, 4260096,9468896,21046464,46779840,103977280, 231109696,513686144,1141767168,2537799168, 5640751232,12537664512,27867393024,61940690176] |