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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 6 |
| 5 | 11 |
| 6 | 20 |
| 7 | 33 |
| 8 | 57 |
| 9 | 100 |
| 10 | 165 |
| 11 | 254 |
| 12 | 417 |
| 13 | 649 |
| 14 | 1039 |
| 15 | 1648 |
| 16 | 2540 |
| 17 | 3836 |
| 18 | 6020 |
| 19 | 9035 |
| 20 | 13645 |
| 21 | 20752 |
| 22 | 31054 |
| 23 | 45993 |
| 24 | 68668 |
| 25 | 101511 |
| 26 | 149525 |
| 27 | 220132 |
| 28 | 321614 |
| 29 | 468031 |
| 30 | 684124 |
| 31 | 989703 |
| 32 | 1427054 |
| 33 | 2064859 |
| 34 | 2964987 |
| 35 | 4254028 |
| 36 | 6090453 |
| 37 | 8686574 |
| 38 | 12366583 |
| 39 | 17598885 |
[0,1,1,4,6,11,20,33,57,100,165,254,417,649,1039, 1648,2540,3836,6020,9035,13645,20752,31054,45993, 68668,101511,149525,220132,321614,468031,684124, 989703,1427054,2064859,2964987,4254028,6090453, 8686574,12366583,17598885] |