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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 2 |
| 3 | 2 |
| 4 | 5 |
| 5 | 9 |
| 6 | 17 |
| 7 | 33 |
| 8 | 62 |
| 9 | 119 |
| 10 | 226 |
| 11 | 431 |
| 12 | 821 |
| 13 | 1564 |
| 14 | 2980 |
| 15 | 5677 |
| 16 | 10816 |
| 17 | 20606 |
| 18 | 39258 |
| 19 | 74793 |
| 20 | 142493 |
| 21 | 271473 |
| 22 | 517201 |
| 23 | 985354 |
| 24 | 1877263 |
| 25 | 3576498 |
| 26 | 6813823 |
| 27 | 12981465 |
| 28 | 24731848 |
| 29 | 47118280 |
| 30 | 89768153 |
| 31 | 171023248 |
| 32 | 325827706 |
| 33 | 620755922 |
| 34 | 1182643181 |
[1,0,2,2,5,9,17,33,62,119,226,431,821,1564,2980, 5677,10816,20606,39258,74793,142493,271473,517201, 985354,1877263,3576498,6813823,12981465,24731848, 47118280,89768153,171023248,325827706,620755922, 1182643181] |