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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 2 |
| 7 | 7 |
| 8 | 9 |
| 9 | 19 |
| 10 | 33 |
| 11 | 64 |
| 12 | 115 |
| 13 | 216 |
| 14 | 402 |
| 15 | 754 |
| 16 | 1434 |
| 17 | 2669 |
| 18 | 5116 |
| 19 | 9651 |
| 20 | 18382 |
| 21 | 35064 |
| 22 | 67056 |
| 23 | 128394 |
| 24 | 246349 |
| 25 | 473469 |
| 26 | 911468 |
| 27 | 1757069 |
| 28 | 3389718 |
| 29 | 6551877 |
| 30 | 12674065 |
| 31 | 24546590 |
| 32 | 47581820 |
| 33 | 92330910 |
| 34 | 179317301 |
| 35 | 348546007 |
| 36 | 678027180 |
| 37 | 1319932246 |
| 38 | 2571422948 |
[0,0,1,1,2,2,7,9,19,33,64,115,216,402,754,1434, 2669,5116,9651,18382,35064,67056,128394,246349, 473469,911468,1757069,3389718,6551877,12674065, 24546590,47581820,92330910,179317301,348546007, 678027180,1319932246,2571422948] |