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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 2 |
| 6 | 1 |
| 7 | 5 |
| 8 | 5 |
| 9 | 15 |
| 10 | 23 |
| 11 | 54 |
| 12 | 98 |
| 13 | 212 |
| 14 | 420 |
| 15 | 886 |
| 16 | 1822 |
| 17 | 3838 |
| 18 | 8046 |
| 19 | 17029 |
| 20 | 36097 |
| 21 | 76889 |
| 22 | 164245 |
| 23 | 351971 |
| 24 | 756341 |
| 25 | 1629389 |
| 26 | 3518643 |
| 27 | 7614717 |
| 28 | 16512962 |
| 29 | 35875986 |
| 30 | 78082171 |
| 31 | 170219300 |
| 32 | 371651968 |
| 33 | 812624721 |
| 34 | 1779240627 |
| 35 | 3900634491 |
| 36 | 8561723769 |
| 37 | 18814112811 |
[1,0,1,0,2,1,5,5,15,23,54,98,212,420,886,1822, 3838,8046,17029,36097,76889,164245,351971,756341, 1629389,3518643,7614717,16512962,35875986, 78082171,170219300,371651968,812624721,1779240627, 3900634491,8561723769,18814112811] |