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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 4 |
| 7 | 7 |
| 8 | 15 |
| 9 | 30 |
| 10 | 68 |
| 11 | 146 |
| 12 | 340 |
| 13 | 786 |
| 14 | 1878 |
| 15 | 4507 |
| 16 | 11045 |
| 17 | 27220 |
| 18 | 67956 |
| 19 | 170766 |
| 20 | 432818 |
| 21 | 1103539 |
| 22 | 2831814 |
| 23 | 7303966 |
| 24 | 18934866 |
| 25 | 49302321 |
| 26 | 128910528 |
| 27 | 338329555 |
| 28 | 891099316 |
| 29 | 2354613762 |
| 30 | 6240696052 |
| 31 | 16587146598 |
| 32 | 44203851675 |
| 33 | 118093003229 |
[0,1,1,1,2,2,4,7,15,30,68,146,340,786,1878,4507, 11045,27220,67956,170766,432818,1103539,2831814, 7303966,18934866,49302321,128910528,338329555, 891099316,2354613762,6240696052,16587146598, 44203851675,118093003229] |