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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 6 |
| 7 | 11 |
| 8 | 16 |
| 9 | 27 |
| 10 | 42 |
| 11 | 65 |
| 12 | 109 |
| 13 | 173 |
| 14 | 304 |
| 15 | 501 |
| 16 | 860 |
| 17 | 1518 |
| 18 | 2678 |
| 19 | 4749 |
| 20 | 8500 |
| 21 | 15320 |
| 22 | 27765 |
| 23 | 50326 |
| 24 | 91996 |
| 25 | 168285 |
| 26 | 309294 |
| 27 | 571477 |
| 28 | 1057147 |
| 29 | 1962048 |
| 30 | 3650516 |
| 31 | 6810112 |
| 32 | 12740284 |
| 33 | 23875506 |
| 34 | 44842400 |
| 35 | 84384850 |
| 36 | 159089621 |
| 37 | 300415965 |
| 38 | 568225074 |
| 39 | 1076428659 |
[0,0,1,2,4,6,11,16,27,42,65,109,173,304,501,860, 1518,2678,4749,8500,15320,27765,50326,91996, 168285,309294,571477,1057147,1962048,3650516, 6810112,12740284,23875506,44842400,84384850, 159089621,300415965,568225074,1076428659] |