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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 5 |
| 6 | 9 |
| 7 | 15 |
| 8 | 25 |
| 9 | 43 |
| 10 | 74 |
| 11 | 126 |
| 12 | 217 |
| 13 | 372 |
| 14 | 638 |
| 15 | 1096 |
| 16 | 1881 |
| 17 | 3230 |
| 18 | 5546 |
| 19 | 9524 |
| 20 | 16353 |
| 21 | 28083 |
| 22 | 48224 |
| 23 | 82811 |
| 24 | 142208 |
| 25 | 244204 |
| 26 | 419360 |
| 27 | 720144 |
| 28 | 1236670 |
| 29 | 2123670 |
| 30 | 3646879 |
| 31 | 6262611 |
| 32 | 10754485 |
| 33 | 18468174 |
| 34 | 31714525 |
| 35 | 54461873 |
| 36 | 93524824 |
| 37 | 160605817 |
| 38 | 275800867 |
[1,1,1,2,3,5,9,15,25,43,74,126,217,372,638,1096, 1881,3230,5546,9524,16353,28083,48224,82811, 142208,244204,419360,720144,1236670,2123670, 3646879,6262611,10754485,18468174,31714525, 54461873,93524824,160605817,275800867] |