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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 2 |
| 6 | 2 |
| 7 | 4 |
| 8 | 6 |
| 9 | 9 |
| 10 | 15 |
| 11 | 20 |
| 12 | 31 |
| 13 | 48 |
| 14 | 72 |
| 15 | 110 |
| 16 | 170 |
| 17 | 257 |
| 18 | 400 |
| 19 | 608 |
| 20 | 950 |
| 21 | 1448 |
| 22 | 2256 |
| 23 | 3487 |
| 24 | 5413 |
| 25 | 8440 |
| 26 | 13118 |
| 27 | 20478 |
| 28 | 31932 |
| 29 | 49995 |
| 30 | 78222 |
| 31 | 122553 |
| 32 | 192262 |
| 33 | 301826 |
| 34 | 474039 |
| 35 | 745772 |
| 36 | 1173270 |
| 37 | 1848000 |
| 38 | 2912623 |
| 39 | 4593723 |
| 40 | 7249438 |
| 41 | 11448047 |
[1,0,1,0,2,2,4,6,9,15,20,31,48,72,110,170,257,400, 608,950,1448,2256,3487,5413,8440,13118,20478, 31932,49995,78222,122553,192262,301826,474039, 745772,1173270,1848000,2912623,4593723,7249438, 11448047] |