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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 9 |
| 6 | 18 |
| 7 | 34 |
| 8 | 71 |
| 9 | 139 |
| 10 | 280 |
| 11 | 555 |
| 12 | 1119 |
| 13 | 2228 |
| 14 | 4462 |
| 15 | 8907 |
| 16 | 17835 |
| 17 | 35634 |
| 18 | 71288 |
| 19 | 142507 |
| 20 | 285077 |
| 21 | 570013 |
| 22 | 1140102 |
| 23 | 2279924 |
| 24 | 4560040 |
| 25 | 9119516 |
| 26 | 18239335 |
| 27 | 36477548 |
| 28 | 72955801 |
| 29 | 145909351 |
| 30 | 291819915 |
| 31 | 583635336 |
| 32 | 1167273283 |
[0,1,2,5,9,18,34,71,139,280,555,1119,2228,4462, 8907,17835,35634,71288,142507,285077,570013, 1140102,2279924,4560040,9119516,18239335,36477548, 72955801,145909351,291819915,583635336,1167273283] |