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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 19 |
| 7 | 46 |
| 8 | 110 |
| 9 | 273 |
| 10 | 684 |
| 11 | 1746 |
| 12 | 4503 |
| 13 | 11758 |
| 14 | 30943 |
| 15 | 82118 |
| 16 | 219337 |
| 17 | 589477 |
| 18 | 1592427 |
| 19 | 4322386 |
| 20 | 11781435 |
| 21 | 32235285 |
| 22 | 88502260 |
| 23 | 243747792 |
| 24 | 673238061 |
| 25 | 1864400173 |
| 26 | 5175591107 |
| 27 | 14399672901 |
| 28 | 40146278964 |
| 29 | 112143682477 |
| 30 | 313822403439 |
| 31 | 879673332422 |
[0,1,1,2,4,9,19,46,110,273,684,1746,4503,11758, 30943,82118,219337,589477,1592427,4322386, 11781435,32235285,88502260,243747792,673238061, 1864400173,5175591107,14399672901,40146278964, 112143682477,313822403439,879673332422] |