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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 16 |
| 4 | 46 |
| 5 | 104 |
| 6 | 268 |
| 7 | 596 |
| 8 | 1406 |
| 9 | 3060 |
| 10 | 6812 |
| 11 | 14356 |
| 12 | 30948 |
| 13 | 63660 |
| 14 | 132328 |
| 15 | 267164 |
| 16 | 541678 |
| 17 | 1072000 |
| 18 | 2127052 |
| 19 | 4140340 |
| 20 | 8060588 |
| 21 | 15458948 |
| 22 | 29602504 |
| 23 | 55990780 |
| 24 | 105693252 |
| 25 | 197422424 |
| 26 | 367793952 |
| 27 | 679206200 |
| 28 | 1250557768 |
| 29 | 2284986580 |
| 30 | 4162202864 |
| 31 | 7530956532 |
| 32 | 13583095710 |
[1,2,6,16,46,104,268,596,1406,3060,6812,14356, 30948,63660,132328,267164,541678,1072000,2127052, 4140340,8060588,15458948,29602504,55990780, 105693252,197422424,367793952,679206200, 1250557768,2284986580,4162202864,7530956532, 13583095710] |