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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 1 |
| 6 | 9 |
| 7 | 11 |
| 8 | 18 |
| 9 | 51 |
| 10 | 65 |
| 11 | 151 |
| 12 | 290 |
| 13 | 477 |
| 14 | 1043 |
| 15 | 1835 |
| 16 | 3486 |
| 17 | 6931 |
| 18 | 12540 |
| 19 | 24607 |
| 20 | 46797 |
| 21 | 87979 |
| 22 | 171072 |
| 23 | 323269 |
| 24 | 619245 |
| 25 | 1190619 |
| 26 | 2264925 |
| 27 | 4357211 |
| 28 | 8343322 |
| 29 | 15973309 |
| 30 | 30711853 |
| 31 | 58846191 |
| 32 | 113027716 |
| 33 | 217192103 |
| 34 | 416964202 |
| 35 | 801880039 |
| 36 | 1541412015 |
| 37 | 2963997227 |
[1,0,1,3,1,9,11,18,51,65,151,290,477,1043,1835, 3486,6931,12540,24607,46797,87979,171072,323269, 619245,1190619,2264925,4357211,8343322,15973309, 30711853,58846191,113027716,217192103,416964202, 801880039,1541412015,2963997227] |