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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 4 |
| 6 | 9 |
| 7 | 15 |
| 8 | 29 |
| 9 | 45 |
| 10 | 94 |
| 11 | 155 |
| 12 | 318 |
| 13 | 548 |
| 14 | 1088 |
| 15 | 1976 |
| 16 | 3812 |
| 17 | 7115 |
| 18 | 13617 |
| 19 | 25733 |
| 20 | 49247 |
| 21 | 93739 |
| 22 | 179691 |
| 23 | 343816 |
| 24 | 660735 |
| 25 | 1270112 |
| 26 | 2448975 |
| 27 | 4727786 |
| 28 | 9146539 |
| 29 | 17717760 |
| 30 | 34366228 |
| 31 | 66718749 |
| 32 | 129619199 |
| 33 | 251958752 |
| 34 | 489959621 |
| 35 | 953155315 |
| 36 | 1854898028 |
[0,1,1,1,3,4,9,15,29,45,94,155,318,548,1088,1976, 3812,7115,13617,25733,49247,93739,179691,343816, 660735,1270112,2448975,4727786,9146539,17717760, 34366228,66718749,129619199,251958752,489959621, 953155315,1854898028] |