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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 2 |
| 5 | 7 |
| 6 | 17 |
| 7 | 40 |
| 8 | 87 |
| 9 | 196 |
| 10 | 413 |
| 11 | 875 |
| 12 | 1812 |
| 13 | 3741 |
| 14 | 7640 |
| 15 | 15567 |
| 16 | 31493 |
| 17 | 63666 |
| 18 | 128284 |
| 19 | 257977 |
| 20 | 518045 |
| 21 | 1039478 |
| 22 | 2083719 |
| 23 | 4174586 |
| 24 | 8359837 |
| 25 | 16735079 |
| 26 | 33493780 |
| 27 | 67020261 |
| 28 | 134090173 |
| 29 | 268250256 |
| 30 | 536609131 |
| 31 | 1073358893 |
| 32 | 2146942626 |
| 33 | 4294183434 |
| 34 | 8588837984 |
| 35 | 17178273355 |
[0,0,0,1,2,7,17,40,87,196,413,875,1812,3741,7640, 15567,31493,63666,128284,257977,518045,1039478, 2083719,4174586,8359837,16735079,33493780, 67020261,134090173,268250256,536609131,1073358893, 2146942626,4294183434,8588837984,17178273355] |