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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 3 |
| 3 | 1 |
| 4 | 4 |
| 5 | 3 |
| 6 | 7 |
| 7 | 14 |
| 8 | 35 |
| 9 | 89 |
| 10 | 242 |
| 11 | 643 |
| 12 | 1713 |
| 13 | 4584 |
| 14 | 12341 |
| 15 | 33393 |
| 16 | 90828 |
| 17 | 247775 |
| 18 | 677335 |
| 19 | 1853786 |
| 20 | 5076655 |
| 21 | 13907485 |
| 22 | 38106762 |
| 23 | 104424087 |
| 24 | 286173877 |
| 25 | 784293860 |
| 26 | 2149515757 |
| 27 | 5891305033 |
| 28 | 16146865524 |
| 29 | 44255648343 |
| 30 | 121297428367 |
| 31 | 332457355358 |
[0,3,1,4,3,7,14,35,89,242,643,1713,4584,12341, 33393,90828,247775,677335,1853786,5076655, 13907485,38106762,104424087,286173877,784293860, 2149515757,5891305033,16146865524,44255648343, 121297428367,332457355358] |