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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 7 |
| 5 | 12 |
| 6 | 21 |
| 7 | 40 |
| 8 | 76 |
| 9 | 139 |
| 10 | 254 |
| 11 | 466 |
| 12 | 855 |
| 13 | 1576 |
| 14 | 2905 |
| 15 | 5340 |
| 16 | 9816 |
| 17 | 18053 |
| 18 | 33202 |
| 19 | 61076 |
| 20 | 112351 |
| 21 | 206636 |
| 22 | 380045 |
| 23 | 699012 |
| 24 | 1285684 |
| 25 | 2364759 |
| 26 | 4349502 |
| 27 | 7999954 |
| 28 | 14714159 |
| 29 | 27063568 |
| 30 | 49777681 |
| 31 | 91555464 |
| 32 | 168396816 |
| 33 | 309729961 |
| 34 | 569682082 |
| 35 | 1047808756 |
[0,1,2,4,7,12,21,40,76,139,254,466,855,1576,2905, 5340,9816,18053,33202,61076,112351,206636,380045, 699012,1285684,2364759,4349502,7999954,14714159, 27063568,49777681,91555464,168396816,309729961, 569682082,1047808756] |