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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 11 |
| 7 | 20 |
| 8 | 40 |
| 9 | 77 |
| 10 | 148 |
| 11 | 285 |
| 12 | 570 |
| 13 | 1120 |
| 14 | 2200 |
| 15 | 4323 |
| 16 | 8498 |
| 17 | 16996 |
| 18 | 33707 |
| 19 | 66844 |
| 20 | 132568 |
| 21 | 262936 |
| 22 | 521549 |
| 23 | 1043098 |
| 24 | 2077698 |
| 25 | 4138400 |
| 26 | 8243093 |
| 27 | 16419342 |
| 28 | 32706116 |
| 29 | 65149296 |
| 30 | 130298592 |
| 31 | 260075635 |
| 32 | 519108172 |
| 33 | 1036138646 |
| 34 | 2068138892 |
| 35 | 4128034691 |
[1,1,2,3,6,11,20,40,77,148,285,570,1120,2200,4323, 8498,16996,33707,66844,132568,262936,521549, 1043098,2077698,4138400,8243093,16419342,32706116, 65149296,130298592,260075635,519108172,1036138646, 2068138892,4128034691] |