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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 10 |
| 6 | 28 |
| 7 | 61 |
| 8 | 152 |
| 9 | 318 |
| 10 | 748 |
| 11 | 1538 |
| 12 | 3496 |
| 13 | 7124 |
| 14 | 15832 |
| 15 | 32093 |
| 16 | 70192 |
| 17 | 141814 |
| 18 | 306508 |
| 19 | 617878 |
| 20 | 1323272 |
| 21 | 2663340 |
| 22 | 5662600 |
| 23 | 11383986 |
| 24 | 24061264 |
| 25 | 48330540 |
| 26 | 101653368 |
| 27 | 204049636 |
| 28 | 427414672 |
| 29 | 857503784 |
| 30 | 1789891888 |
| 31 | 3589478621 |
| 32 | 7469802592 |
| 33 | 14974962854 |
| 34 | 31081371148 |
[0,0,0,1,4,10,28,61,152,318,748,1538,3496,7124, 15832,32093,70192,141814,306508,617878,1323272, 2663340,5662600,11383986,24061264,48330540, 101653368,204049636,427414672,857503784, 1789891888,3589478621,7469802592,14974962854, 31081371148] |