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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 6 |
| 5 | 10 |
| 6 | 13 |
| 7 | 20 |
| 8 | 21 |
| 9 | 33 |
| 10 | 54 |
| 11 | 86 |
| 12 | 146 |
| 13 | 339 |
| 14 | 788 |
| 15 | 2947 |
| 16 | 14870 |
| 17 | 94801 |
| 18 | 706961 |
| 19 | 5566784 |
| 20 | 43958933 |
| 21 | 317950465 |
| 22 | 2406052444 |
| 23 | 19645433193 |
| 24 | 146175038733 |
| 25 | 1479263447899 |
| 26 | 16135114175706 |
| 27 | 203382520812382 |
| 28 | 2606355260220040 |
| 29 | 32974597626726301 |
| 30 | 406609097787758227 |
[0,1,2,4,6,10,13,20,21,33,54,86,146,339,788,2947, 14870,94801,706961,5566784,43958933,317950465, 2406052444,19645433193,146175038733,1479263447899, 16135114175706,203382520812382,2606355260220040, 32974597626726301,406609097787758227] |