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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 4 |
| 7 | 7 |
| 8 | 13 |
| 9 | 27 |
| 10 | 54 |
| 11 | 112 |
| 12 | 243 |
| 13 | 538 |
| 14 | 1223 |
| 15 | 2875 |
| 16 | 6909 |
| 17 | 17052 |
| 18 | 43138 |
| 19 | 111686 |
| 20 | 295658 |
| 21 | 799684 |
| 22 | 2207356 |
| 23 | 6213391 |
| 24 | 17820961 |
| 25 | 52042771 |
| 26 | 154640528 |
| 27 | 467254731 |
| 28 | 1434837672 |
| 29 | 4475520062 |
| 30 | 14173115724 |
| 31 | 45548395180 |
| 32 | 148485883443 |
| 33 | 490831193397 |
| 34 | 1644581336531 |
[1,0,0,1,1,2,4,7,13,27,54,112,243,538,1223,2875, 6909,17052,43138,111686,295658,799684,2207356, 6213391,17820961,52042771,154640528,467254731, 1434837672,4475520062,14173115724,45548395180, 148485883443,490831193397,1644581336531] |