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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 10 |
| 6 | 30 |
| 7 | 26 |
| 8 | 78 |
| 9 | 156 |
| 10 | 278 |
| 11 | 722 |
| 12 | 1827 |
| 13 | 3140 |
| 14 | 7800 |
| 15 | 5810 |
| 16 | 21016 |
| 17 | 40260 |
| 18 | 76104 |
| 19 | 173836 |
| 20 | 394492 |
| 21 | 520775 |
| 22 | 1376090 |
| 23 | 3080882 |
| 24 | 6887040 |
| 25 | 12734023 |
| 26 | 28266044 |
| 27 | 44217698 |
| 28 | 114969792 |
| 29 | 211934801 |
| 30 | 464129402 |
| 31 | 354151217 |
| 32 | 1360414116 |
| 33 | 2644465928 |
| 34 | 5134476403 |
[0,1,1,2,4,10,30,26,78,156,278,722,1827,3140,7800, 5810,21016,40260,76104,173836,394492,520775, 1376090,3080882,6887040,12734023,28266044, 44217698,114969792,211934801,464129402,354151217, 1360414116,2644465928,5134476403] |