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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 4 |
| 7 | 4 |
| 8 | 7 |
| 9 | 8 |
| 10 | 13 |
| 11 | 15 |
| 12 | 25 |
| 13 | 30 |
| 14 | 48 |
| 15 | 63 |
| 16 | 98 |
| 17 | 132 |
| 18 | 208 |
| 19 | 290 |
| 20 | 454 |
| 21 | 656 |
| 22 | 1021 |
| 23 | 1509 |
| 24 | 2358 |
| 25 | 3544 |
| 26 | 5535 |
| 27 | 8441 |
| 28 | 13200 |
| 29 | 20318 |
| 30 | 31835 |
| 31 | 49352 |
| 32 | 77435 |
| 33 | 120710 |
| 34 | 189673 |
| 35 | 296853 |
| 36 | 467159 |
| 37 | 733362 |
| 38 | 1155646 |
| 39 | 1818593 |
| 40 | 2869377 |
| 41 | 4524080 |
[0,1,1,2,2,4,4,7,8,13,15,25,30,48,63,98,132,208, 290,454,656,1021,1509,2358,3544,5535,8441,13200, 20318,31835,49352,77435,120710,189673,296853, 467159,733362,1155646,1818593,2869377,4524080] |