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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 3 |
| 6 | 5 |
| 7 | 14 |
| 8 | 28 |
| 9 | 75 |
| 10 | 170 |
| 11 | 443 |
| 12 | 1076 |
| 13 | 2795 |
| 14 | 7046 |
| 15 | 18398 |
| 16 | 47458 |
| 17 | 124793 |
| 18 | 326905 |
| 19 | 865853 |
| 20 | 2293103 |
| 21 | 6114688 |
| 22 | 16327765 |
| 23 | 43800590 |
| 24 | 117720693 |
| 25 | 317452606 |
| 26 | 857742087 |
| 27 | 2323588888 |
| 28 | 6306229600 |
| 29 | 17151172495 |
| 30 | 46725729232 |
| 31 | 127522337636 |
| 32 | 348562660876 |
[1,0,1,1,3,5,14,28,75,170,443,1076,2795,7046, 18398,47458,124793,326905,865853,2293103,6114688, 16327765,43800590,117720693,317452606,857742087, 2323588888,6306229600,17151172495,46725729232, 127522337636,348562660876] |