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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 5 |
| 5 | 6 |
| 6 | 15 |
| 7 | 36 |
| 8 | 108 |
| 9 | 301 |
| 10 | 814 |
| 11 | 2080 |
| 12 | 5223 |
| 13 | 12919 |
| 14 | 32557 |
| 15 | 83943 |
| 16 | 222591 |
| 17 | 600252 |
| 18 | 1632814 |
| 19 | 4440240 |
| 20 | 12043224 |
| 21 | 32572225 |
| 22 | 88081208 |
| 23 | 238722759 |
| 24 | 649725756 |
| 25 | 1776546687 |
| 26 | 4877740703 |
| 27 | 13432630929 |
| 28 | 37063472432 |
| 29 | 102389547753 |
[1,1,2,3,5,6,15,36,108,301,814,2080,5223,12919, 32557,83943,222591,600252,1632814,4440240, 12043224,32572225,88081208,238722759,649725756, 1776546687,4877740703,13432630929,37063472432, 102389547753] |